Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59377)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -123,6 +123,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +141,11 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -154,6 +164,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -263,6 +274,7 @@
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
     fUpdateLayout: integer;
+    FMinimized: boolean;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +331,7 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -2193,7 +2206,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -3680,6 +3693,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -5165,6 +5179,59 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+var
+  AControl: TControl;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  SpliterPercentPosition:Single;
+begin
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  AControl:=GetOneControl;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then
+    if Splitter.Enabled or FMinimized then begin
+      FMinimized:=not FMinimized;
+      AControl.Visible:=not AControl.Visible;
+      Splitter.Enabled:=AControl.Visible;
+      if FMinimized then begin
+        SpliterPercentPosition:=Splitter.FPercentPosition;
+        UpdateHeaderAlign;
+        case SplitterAnchorKind of
+          akTop: Splitter.MoveSplitter(Height-Header.Height);
+          akBottom: Splitter.MoveSplitter(Header.Height-Splitter.Top);
+          akLeft: Splitter.MoveSplitter(Header.Height-Splitter.Left);
+          akRight: Splitter.MoveSplitter(Width-Header.Height);
+        end;
+        Splitter.FPercentPosition:=SpliterPercentPosition;
+      end else begin
+        UpdateHeaderAlign;
+      end;
+    end;
+end;
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5306,9 +5373,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm))and(Pages=nil);
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5362,9 +5428,27 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+const
+OppositeAlign: array[TAnchorKind] of TAlign = (
+  alBottom, // akTop,
+  alRight,  // akLeft,
+  alLeft,   // akRight,
+  alTop     // akBottom
+  );
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      Header.Align:=OppositeAlign[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5476,6 +5560,7 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5569,6 +5654,13 @@
   end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+begin
+  if Parent is TAnchorDockHostSite then begin
+    TAnchorDockHostSite(Parent).MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5640,6 +5732,13 @@
       r.Right:=CloseButton.Left-1;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+1
+    else
+      r.Right:=MinimizeButton.Left-1;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,7 +5827,14 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
@@ -5742,11 +5848,15 @@
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alTop;
       CloseButton.Align:=alTop;
+    end;
   end else begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alRight;
       CloseButton.Align:=alRight;
+    end;
   end;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
@@ -5787,9 +5897,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,6 +5909,16 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
@@ -5844,6 +5964,44 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMDIMinButtonNormal;
+    if not IsEnabled then
+      Result := twMDIMinButtonDisabled
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := twMDIMinButtonPushed
+    else
+    if FState = bsHot then
+      Result := twMDIMinButtonHot
+    else
+      Result := twMDIMinButtonNormal;
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails(twMinButtonNormal)) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6506,31 +6664,33 @@
 var
   NewLeft, NewTop: Integer;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
-    end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
     begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59377)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59377)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -123,6 +123,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +141,11 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -154,6 +164,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -263,6 +274,7 @@
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
     fUpdateLayout: integer;
+    FMinimized: boolean;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +331,7 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -970,6 +983,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -2193,7 +2227,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -3680,6 +3714,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -5165,6 +5200,63 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  AControl:=GetOneControl;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) or FMinimized then begin
+      FMinimized:=not FMinimized;
+      AControl.Visible:=not AControl.Visible;
+      Splitter.Enabled:=AControl.Visible;
+      UpdateHeaderAlign;
+      {if FMinimized then begin
+        SpliterPercentPosition:=Splitter.FPercentPosition;
+        UpdateHeaderAlign;
+        case SplitterAnchorKind of
+          akTop: Splitter.MoveSplitter(Height-Header.Height);
+          akBottom: Splitter.MoveSplitter(Header.Height-Splitter.Top);
+          akLeft: Splitter.MoveSplitter(Header.Height-Splitter.Left);
+          akRight: Splitter.MoveSplitter(Width-Header.Height);
+        end;
+        Splitter.FPercentPosition:=SpliterPercentPosition;
+      end else begin
+        UpdateHeaderAlign;
+      end;}
+    end;
+  end;
+end;
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5306,9 +5398,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm))and(Pages=nil);
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5362,9 +5453,27 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+const
+OppositeAlign: array[TAnchorKind] of TAlign = (
+  alBottom, // akTop,
+  alRight,  // akLeft,
+  alLeft,   // akRight,
+  alTop     // akBottom
+  );
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      Header.Align:=OppositeAlign[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5476,6 +5585,7 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5569,6 +5679,13 @@
   end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+begin
+  if Parent is TAnchorDockHostSite then begin
+    TAnchorDockHostSite(Parent).MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5640,6 +5757,13 @@
       r.Right:=CloseButton.Left-1;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+1
+    else
+      r.Right:=MinimizeButton.Left-1;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,7 +5852,14 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
@@ -5742,11 +5873,15 @@
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alTop;
       CloseButton.Align:=alTop;
+    end;
   end else begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alRight;
       CloseButton.Align:=alRight;
+    end;
   end;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
@@ -5787,9 +5922,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,6 +5934,16 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
@@ -5844,6 +5989,44 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMDIMinButtonNormal;
+    if not IsEnabled then
+      Result := twMDIMinButtonDisabled
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := twMDIMinButtonPushed
+    else
+    if FState = bsHot then
+      Result := twMDIMinButtonHot
+    else
+      Result := twMDIMinButtonNormal;
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails(twMinButtonNormal)) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6505,32 +6688,57 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59377)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59377)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -123,6 +123,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +141,11 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -154,6 +164,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -263,6 +274,7 @@
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
     fUpdateLayout: integer;
+    FMinimized: boolean;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +331,7 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -431,6 +444,7 @@
     FShowHeader: boolean;
     FShowHeaderCaption: boolean;
     FSplitterWidth: integer;
+    FDockSitecCanBeMinimized: boolean;
     procedure SetAllowDragging(AValue: boolean);
     procedure SetDockOutsideMargin(AValue: integer);
     procedure SetDockParentMargin(AValue: integer);
@@ -448,6 +462,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitecCanBeMinimized(AValue: boolean);
   public
     property DragTreshold: integer read FDragTreshold write SetDragTreshold;
     property DockOutsideMargin: integer read FDockOutsideMargin write SetDockOutsideMargin;
@@ -466,6 +481,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused;
+    property DockSitesCanBeMinimized: boolean read FDockSitecCanBeMinimized write SetDockSitecCanBeMinimized;
     procedure IncreaseChangeStamp; inline;
     property ChangeStamp: integer read FChangeStamp;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
@@ -502,6 +518,7 @@
     FHeaderFlatten: boolean;
     FHeaderFilled: boolean;
     FHeaderHighlightFocused: boolean;
+    FDockSitesCanBeMinimized: boolean;
     FIdleConnected: Boolean;
     FManagerClass: TAnchorDockManagerClass;
     FOnCreateControl: TADCreateControlEvent;
@@ -561,6 +578,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitesCanBeMinimized(AValue: boolean);
 
     procedure SetShowMenuItemShowHeader(AValue: boolean);
     procedure SetupSite(Site: TWinControl; ANode: TAnchorDockLayoutTreeNode;
@@ -680,6 +698,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten default true;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled default true;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused default false;
+    property DockSitesCanBeMinimized: boolean read FDockSitesCanBeMinimized write SetDockSitesCanBeMinimized default false;
 
     property SplitterWidth: integer read FSplitterWidth write SetSplitterWidth default 4;
     property ScaleOnResize: boolean read FScaleOnResize write SetScaleOnResize default true; // scale children when resizing a site
@@ -970,6 +989,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -1361,6 +1401,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockSettings.SetDockSitecCanBeMinimized(AValue: boolean);
+begin
+  if FDockSitecCanBeMinimized=AValue then Exit;
+  FDockSitecCanBeMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockSettings.Assign(Source: TAnchorDockSettings);
 begin
   FAllowDragging := Source.FAllowDragging;
@@ -1381,6 +1428,7 @@
   FShowHeaderCaption := Source.FShowHeaderCaption;
   FSplitterWidth := Source.FSplitterWidth;
   FHeaderHighlightFocused:=Source.FHeaderHighlightFocused;
+  FDockSitecCanBeMinimized:=Source.FDockSitecCanBeMinimized;
 end;
 
 procedure TAnchorDockSettings.IncreaseChangeStamp;
@@ -1407,6 +1455,7 @@
   HeaderFlatten:=Config.GetValue('HeaderFlatten',true);
   HeaderFilled:=Config.GetValue('HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue('HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue('DockSitecCanBeMinimized',False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1429,6 +1478,7 @@
   Config.SetDeleteValue(Path+'HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue(Path+'HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue(Path+'HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue(Path+'DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
 end;
 
 procedure TAnchorDockSettings.SaveToConfig(Config: TConfigStorage);
@@ -1450,6 +1500,7 @@
   Config.SetDeleteValue('HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue('HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue('HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue('DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1472,6 +1523,7 @@
       and (HeaderFlatten=Settings.HeaderFlatten)
       and (HeaderFilled=Settings.HeaderFilled)
       and (HeaderHighlightFocused=Settings.HeaderHighlightFocused)
+      and (DockSitesCanBeMinimized=Settings.DockSitesCanBeMinimized)
       ;
 end;
 
@@ -1494,6 +1546,7 @@
   HeaderFlatten:=Config.GetValue(Path+'HeaderFlatten',true);
   HeaderFilled:=Config.GetValue(Path+'HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue(Path+'HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue(Path+'DockSitecCanBeMinimized',False);
 end;
 
 { TAnchorDockMaster }
@@ -2193,7 +2246,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -2514,6 +2567,24 @@
   InvalidateHeaders;
 end;
 
+procedure TAnchorDockMaster.SetDockSitesCanBeMinimized(AValue: boolean);
+var
+  i:integer;
+  Site: TAnchorDockHostSite;
+begin
+  if FDockSitesCanBeMinimized=AValue then Exit;
+  FDockSitesCanBeMinimized:=AValue;
+  for i:=0 to ComponentCount-1 do begin
+    Site:=TAnchorDockHostSite(Components[i]);
+    if not (Site is TAnchorDockHostSite) then continue;
+    if (Site.Header<>nil) then begin
+      DisableControlAutoSizing(Site);
+      Site.UpdateHeaderShowing;
+    end;
+  end;
+  EnableAllAutoSizing;
+  OptionsChanged;
+end;
 procedure TAnchorDockMaster.SetScaleOnResize(AValue: boolean);
 begin
   if FScaleOnResize=AValue then Exit;
@@ -2698,6 +2769,7 @@
   FPageClass:=TAnchorDockPage;
   FRestoreLayouts:=TAnchorDockRestoreLayouts.Create;
   FHeaderHighlightFocused:=false;
+  FDockSitesCanBeMinimized:=false;
 end;
 
 destructor TAnchorDockMaster.Destroy;
@@ -3323,6 +3395,7 @@
   HeaderFlatten                    := Settings.HeaderFlatten;
   HeaderFilled                     := Settings.HeaderFilled;
   HeaderHighlightFocused           := Settings.HeaderHighlightFocused;
+  DockSitesCanBeMinimized          := Settings.DockSitesCanBeMinimized;
 end;
 
 procedure TAnchorDockMaster.SaveSettings(Settings: TAnchorDockSettings);
@@ -3343,6 +3416,7 @@
   Settings.HeaderFlatten:=HeaderFlatten;
   Settings.HeaderFilled:=HeaderFilled;
   Settings.HeaderHighlightFocused:=HeaderHighlightFocused;
+  Settings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized;
 end;
 
 function TAnchorDockMaster.SettingsAreEqual(Settings: TAnchorDockSettings
@@ -3680,6 +3754,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -5165,6 +5240,64 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  AControl:=GetOneControl;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) or FMinimized then begin
+      FMinimized:=not FMinimized;
+      AControl.Visible:=not AControl.Visible;
+      Splitter.Enabled:=AControl.Visible;
+      UpdateHeaderAlign;
+      Splitter.SetBoundsPercentually;
+      {if FMinimized then begin
+        SpliterPercentPosition:=Splitter.FPercentPosition;
+        UpdateHeaderAlign;
+        case SplitterAnchorKind of
+          akTop: Splitter.MoveSplitter(Height-Header.Height);
+          akBottom: Splitter.MoveSplitter(Header.Height-Splitter.Top);
+          akLeft: Splitter.MoveSplitter(Header.Height-Splitter.Left);
+          akRight: Splitter.MoveSplitter(Width-Header.Height);
+        end;
+        Splitter.FPercentPosition:=SpliterPercentPosition;
+      end else begin
+        UpdateHeaderAlign;
+      end;}
+    end;
+  end;
+end;
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5306,9 +5439,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm))and(Pages=nil);
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5362,9 +5494,27 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+const
+OppositeAlign: array[TAnchorKind] of TAlign = (
+  alBottom, // akTop,
+  alRight,  // akLeft,
+  alLeft,   // akRight,
+  alTop     // akBottom
+  );
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      Header.Align:=OppositeAlign[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5390,8 +5540,10 @@
 procedure TAnchorDockHostSite.UpdateHeaderShowing;
 begin
   if Header=nil then exit;
-  if HeaderNeedsShowing then
-    Header.Parent:=Self
+  if HeaderNeedsShowing then begin
+    Header.Parent:=Self;
+    Header.MinimizeButton.Visible:=DockMaster.DockSitesCanBeMinimized;
+  end
   else
     Header.Parent:=nil;
 end;
@@ -5476,6 +5628,7 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5569,6 +5722,13 @@
   end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+begin
+  if Parent is TAnchorDockHostSite then begin
+    TAnchorDockHostSite(Parent).MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5640,6 +5800,13 @@
       r.Right:=CloseButton.Left-1;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+1
+    else
+      r.Right:=MinimizeButton.Left-1;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,7 +5895,14 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
@@ -5742,11 +5916,15 @@
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alTop;
       CloseButton.Align:=alTop;
+    end;
   end else begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alRight;
       CloseButton.Align:=alRight;
+    end;
   end;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
@@ -5787,9 +5965,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,6 +5977,16 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
@@ -5844,6 +6032,44 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMDIMinButtonNormal;
+    if not IsEnabled then
+      Result := twMDIMinButtonDisabled
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := twMDIMinButtonPushed
+    else
+    if FState = bsHot then
+      Result := twMDIMinButtonHot
+    else
+      Result := twMDIMinButtonNormal;
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails(twMinButtonNormal)) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6505,32 +6731,58 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
Index: components/anchordocking/anchordockoptionsdlg.lfm
===================================================================
--- components/anchordocking/anchordockoptionsdlg.lfm	(revision 59377)
+++ components/anchordocking/anchordockoptionsdlg.lfm	(working copy)
@@ -1,11 +1,13 @@
 object AnchorDockOptionsFrame: TAnchorDockOptionsFrame
   Left = 0
-  Height = 482
+  Height = 567
   Top = 0
-  Width = 416
-  ClientHeight = 482
-  ClientWidth = 416
+  Width = 490
+  ClientHeight = 567
+  ClientWidth = 490
+  DesignTimePPI = 113
   OnClick = FrameClick
+  ParentFont = False
   TabOrder = 0
   DesignLeft = 513
   DesignTop = 189
@@ -12,14 +14,15 @@
   object DragThresholdLabel: TLabel
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
-    Left = 10
-    Height = 13
-    Top = 10
-    Width = 111
-    BorderSpacing.Left = 10
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 12
+    Width = 122
+    BorderSpacing.Left = 12
+    BorderSpacing.Top = 12
     Caption = 'DragThresholdLabel'
     ParentColor = False
+    ParentFont = False
   end
   object DragThresholdTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdLabel
@@ -27,15 +30,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 23
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 31
+    Width = 466
     Max = 20
     OnChange = DragThresholdTrackBarChange
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Right = 10
+    BorderSpacing.Right = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 1
@@ -46,12 +50,13 @@
     AnchorSideTop.Control = DragThresholdLabel
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
-    Left = 127
-    Height = 23
-    Top = 5
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 141
+    Height = 27
+    Top = 8
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 20
+    ParentFont = False
     TabOrder = 0
     Visible = False
   end
@@ -59,13 +64,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = DragThresholdTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 79
-    Width = 103
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 97
+    Width = 112
+    BorderSpacing.Top = 12
     Caption = 'SplitterWidthLabel'
     ParentColor = False
+    ParentFont = False
   end
   object SplitterWidthTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdTrackBar
@@ -73,14 +79,15 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 92
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 116
+    Width = 466
     Min = 1
     OnChange = SplitterWidthTrackBarChange
     Position = 1
     Anchors = [akTop, akLeft, akRight]
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 3
@@ -89,12 +96,13 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = SplitterWidthTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 142
-    Width = 160
-    BorderSpacing.Top = 4
+    Left = 12
+    Height = 23
+    Top = 175
+    Width = 169
+    BorderSpacing.Top = 5
     Caption = 'ScaleOnResizeCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 4
@@ -103,12 +111,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 166
-    Width = 149
+    Left = 12
+    Height = 23
+    Top = 198
+    Width = 160
     Caption = 'ShowHeaderCheckBox'
     OnChange = ShowHeaderCheckBoxChange
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 5
@@ -117,12 +126,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ShowHeaderCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 190
-    Width = 191
-    BorderSpacing.Left = 15
+    Left = 30
+    Height = 23
+    Top = 221
+    Width = 208
+    BorderSpacing.Left = 18
     Caption = 'ShowHeaderCaptionCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 6
@@ -131,11 +141,12 @@
     AnchorSideLeft.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 214
-    Width = 249
+    Left = 30
+    Height = 23
+    Top = 244
+    Width = 272
     Caption = 'HideHeaderCaptionForFloatingCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 7
@@ -147,15 +158,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 122
+    Left = 136
     Height = 27
-    Top = 286
-    Width = 284
+    Top = 313
+    Width = 342
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 6
-    BorderSpacing.Right = 10
-    ItemHeight = 0
+    BorderSpacing.Left = 7
+    BorderSpacing.Right = 12
+    ItemHeight = 19
     OnDrawItem = HeaderStyleComboBoxDrawItem
+    ParentFont = False
     Style = csDropDownList
     TabOrder = 10
   end
@@ -163,23 +175,25 @@
     AnchorSideLeft.Control = ShowHeaderCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrCenter
-    Left = 20
-    Height = 13
-    Top = 293
-    Width = 96
-    BorderSpacing.Left = 10
+    Left = 24
+    Height = 19
+    Top = 317
+    Width = 105
+    BorderSpacing.Left = 12
     Caption = 'HeaderStyleLabel'
     ParentColor = False
+    ParentFont = False
   end
   object FlattenHeadersCheckBox: TCheckBox
     AnchorSideLeft.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 238
-    Width = 164
+    Left = 30
+    Height = 23
+    Top = 267
+    Width = 175
     Caption = 'FlattenHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 8
@@ -188,11 +202,12 @@
     AnchorSideLeft.Control = FlattenHeadersCheckBox
     AnchorSideTop.Control = FlattenHeadersCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 262
-    Width = 154
+    Left = 30
+    Height = 23
+    Top = 290
+    Width = 164
     Caption = 'FilledHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 9
@@ -201,11 +216,12 @@
     AnchorSideLeft.Control = FilledHeadersCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 313
-    Width = 175
+    Left = 30
+    Height = 23
+    Top = 340
+    Width = 189
     Caption = 'HighlightFocusedCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 11
@@ -215,13 +231,14 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = SplitterWidthLabel
     AnchorSideTop.Side = asrCenter
-    Left = 119
-    Height = 23
-    Top = 74
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 131
+    Height = 27
+    Top = 93
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 10
     MinValue = 1
+    ParentFont = False
     TabOrder = 2
     Value = 1
     Visible = False
@@ -228,15 +245,16 @@
   end
   object HeaderAlignTopLabel: TLabel
     AnchorSideLeft.Control = DragThresholdLabel
-    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Control = DockSitesCanBeMinimized
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 347
-    Width = 117
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 398
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignTopLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignTopTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -244,10 +262,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 360
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 417
+    Width = 466
     Frequency = 10
     Max = 150
     OnChange = HeaderAlignTopTrackBarChange
@@ -254,7 +272,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 13
@@ -264,12 +283,13 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignTopLabel
     AnchorSideTop.Side = asrCenter
-    Left = 133
-    Height = 23
-    Top = 342
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 394
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 150
+    ParentFont = False
     TabOrder = 12
     Visible = False
   end
@@ -277,13 +297,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = HeaderAlignTopTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 417
-    Width = 120
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 484
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignLeftLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignLeftTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -291,10 +312,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 430
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 503
+    Width = 466
     Frequency = 10
     Max = 200
     OnChange = HeaderAlignLeftTrackBarChange
@@ -301,7 +322,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 15
@@ -311,13 +333,28 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignLeftLabel
     AnchorSideTop.Side = asrCenter
-    Left = 136
-    Height = 23
-    Top = 412
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 480
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 200
+    ParentFont = False
     TabOrder = 14
     Visible = False
   end
+  object DockSitesCanBeMinimized: TCheckBox
+    AnchorSideLeft.Control = FilledHeadersCheckBox
+    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Side = asrBottom
+    Left = 30
+    Height = 23
+    Top = 363
+    Width = 185
+    Caption = 'DockSitesCanBeMinimized'
+    ParentFont = False
+    ParentShowHint = False
+    ShowHint = True
+    TabOrder = 16
+  end
 end
Index: components/anchordocking/anchordockoptionsdlg.pas
===================================================================
--- components/anchordocking/anchordockoptionsdlg.pas	(revision 59377)
+++ components/anchordocking/anchordockoptionsdlg.pas	(working copy)
@@ -37,6 +37,7 @@
     HeaderStyleLabel: TLabel;
     HideHeaderCaptionForFloatingCheckBox: TCheckBox;
     HighlightFocusedCheckBox: TCheckBox;
+    DockSitesCanBeMinimized: TCheckBox;
     ScaleOnResizeCheckBox: TCheckBox;
     ShowHeaderCaptionCheckBox: TCheckBox;
     ShowHeaderCheckBox: TCheckBox;
@@ -299,6 +300,7 @@
   HeaderStyleLabel.Enabled:=HasHeaders;
   HeaderStyleComboBox.Enabled:=HasHeaders;
   HighlightFocusedCheckBox.Enabled:=HasHeaders;
+  DockSitesCanBeMinimized.Enabled:=HasHeaders;
 end;
 
 constructor TAnchorDockOptionsFrame.Create(TheOwner: TComponent);
@@ -356,6 +358,7 @@
   TheSettings.HeaderFilled:=FilledHeadersCheckBox.Checked;
   TheSettings.HeaderStyle:=TADHeaderStyle(HeaderStyleComboBox.ItemIndex);
   TheSettings.HeaderHighlightFocused:=HighlightFocusedCheckBox.Checked;
+  TheSettings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized.Checked;
 end;
 
 procedure TAnchorDockOptionsFrame.LoadFromSettings(
@@ -429,6 +432,10 @@
   HighlightFocusedCheckBox.Checked:=TheSettings.HeaderHighlightFocused;
   HighlightFocusedCheckBox.Caption:=adrsHighlightFocused;
   HighlightFocusedCheckBox.Hint:=adrsHighlightFocusedHint;
+
+  DockSitesCanBeMinimized.Checked:=TheSettings.DockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Caption:=adrsDockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Hint:=adrsDockSitesCanBeMinimizedHint;
 end;
 
 end.
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59377)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';
@@ -82,6 +83,8 @@
   adrsFilledHeadersHint = 'Fill headers of docked controls';
   adrsHighlightFocused = 'Highlight focused';
   adrsHighlightFocusedHint = 'Highlight header of focused docked control';
+  adrsDockSitesCanBeMinimized = 'Dock sites can be minimized';
+  adrsDockSitesCanBeMinimizedHint = 'Dock sites can be minimized';
 
 implementation
 

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59428)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -123,6 +123,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +141,11 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -154,6 +164,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -262,7 +273,10 @@
     FPages: TAnchorDockPageControl;
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
-    fUpdateLayout: integer;
+    fUpdateLayout: Integer;
+    FMinimized: Boolean;
+    fMinimization: Boolean;
+    FMinimizedControl: TControl;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +333,8 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
+    procedure AsyncMinimizeSite(Data: PtrInt);
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -431,6 +447,7 @@
     FShowHeader: boolean;
     FShowHeaderCaption: boolean;
     FSplitterWidth: integer;
+    FDockSitecCanBeMinimized: boolean;
     procedure SetAllowDragging(AValue: boolean);
     procedure SetDockOutsideMargin(AValue: integer);
     procedure SetDockParentMargin(AValue: integer);
@@ -448,6 +465,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitecCanBeMinimized(AValue: boolean);
   public
     property DragTreshold: integer read FDragTreshold write SetDragTreshold;
     property DockOutsideMargin: integer read FDockOutsideMargin write SetDockOutsideMargin;
@@ -466,6 +484,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused;
+    property DockSitesCanBeMinimized: boolean read FDockSitecCanBeMinimized write SetDockSitecCanBeMinimized;
     procedure IncreaseChangeStamp; inline;
     property ChangeStamp: integer read FChangeStamp;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
@@ -502,6 +521,7 @@
     FHeaderFlatten: boolean;
     FHeaderFilled: boolean;
     FHeaderHighlightFocused: boolean;
+    FDockSitesCanBeMinimized: boolean;
     FIdleConnected: Boolean;
     FManagerClass: TAnchorDockManagerClass;
     FOnCreateControl: TADCreateControlEvent;
@@ -561,6 +581,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitesCanBeMinimized(AValue: boolean);
 
     procedure SetShowMenuItemShowHeader(AValue: boolean);
     procedure SetupSite(Site: TWinControl; ANode: TAnchorDockLayoutTreeNode;
@@ -680,6 +701,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten default true;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled default true;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused default false;
+    property DockSitesCanBeMinimized: boolean read FDockSitesCanBeMinimized write SetDockSitesCanBeMinimized default false;
 
     property SplitterWidth: integer read FSplitterWidth write SetSplitterWidth default 4;
     property ScaleOnResize: boolean read FScaleOnResize write SetScaleOnResize default true; // scale children when resizing a site
@@ -970,6 +992,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -1361,6 +1404,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockSettings.SetDockSitecCanBeMinimized(AValue: boolean);
+begin
+  if FDockSitecCanBeMinimized=AValue then Exit;
+  FDockSitecCanBeMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockSettings.Assign(Source: TAnchorDockSettings);
 begin
   FAllowDragging := Source.FAllowDragging;
@@ -1381,6 +1431,7 @@
   FShowHeaderCaption := Source.FShowHeaderCaption;
   FSplitterWidth := Source.FSplitterWidth;
   FHeaderHighlightFocused:=Source.FHeaderHighlightFocused;
+  FDockSitecCanBeMinimized:=Source.FDockSitecCanBeMinimized;
 end;
 
 procedure TAnchorDockSettings.IncreaseChangeStamp;
@@ -1407,6 +1458,7 @@
   HeaderFlatten:=Config.GetValue('HeaderFlatten',true);
   HeaderFilled:=Config.GetValue('HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue('HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue('DockSitecCanBeMinimized',False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1429,6 +1481,7 @@
   Config.SetDeleteValue(Path+'HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue(Path+'HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue(Path+'HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue(Path+'DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
 end;
 
 procedure TAnchorDockSettings.SaveToConfig(Config: TConfigStorage);
@@ -1450,6 +1503,7 @@
   Config.SetDeleteValue('HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue('HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue('HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue('DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1472,6 +1526,7 @@
       and (HeaderFlatten=Settings.HeaderFlatten)
       and (HeaderFilled=Settings.HeaderFilled)
       and (HeaderHighlightFocused=Settings.HeaderHighlightFocused)
+      and (DockSitesCanBeMinimized=Settings.DockSitesCanBeMinimized)
       ;
 end;
 
@@ -1494,6 +1549,7 @@
   HeaderFlatten:=Config.GetValue(Path+'HeaderFlatten',true);
   HeaderFilled:=Config.GetValue(Path+'HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue(Path+'HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue(Path+'DockSitecCanBeMinimized',False);
 end;
 
 { TAnchorDockMaster }
@@ -2193,7 +2249,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -2514,6 +2570,24 @@
   InvalidateHeaders;
 end;
 
+procedure TAnchorDockMaster.SetDockSitesCanBeMinimized(AValue: boolean);
+var
+  i:integer;
+  Site: TAnchorDockHostSite;
+begin
+  if FDockSitesCanBeMinimized=AValue then Exit;
+  FDockSitesCanBeMinimized:=AValue;
+  for i:=0 to ComponentCount-1 do begin
+    Site:=TAnchorDockHostSite(Components[i]);
+    if not (Site is TAnchorDockHostSite) then continue;
+    if (Site.Header<>nil) then begin
+      DisableControlAutoSizing(Site);
+      Site.UpdateHeaderShowing;
+    end;
+  end;
+  EnableAllAutoSizing;
+  OptionsChanged;
+end;
 procedure TAnchorDockMaster.SetScaleOnResize(AValue: boolean);
 begin
   if FScaleOnResize=AValue then Exit;
@@ -2698,14 +2772,13 @@
   FPageClass:=TAnchorDockPage;
   FRestoreLayouts:=TAnchorDockRestoreLayouts.Create;
   FHeaderHighlightFocused:=false;
+  FDockSitesCanBeMinimized:=false;
 end;
 
 destructor TAnchorDockMaster.Destroy;
 var
   AControl: TControl;
-  {$IFDEF VerboseAnchorDocking}
-  i: Integer;
-  {$ENDIF}
+  i, j: Integer;
 begin
   QueueSimplify:=false;
   FreeAndNil(FRestoreLayouts);
@@ -2727,6 +2800,12 @@
     debugln(['TAnchorDockMaster.Destroy ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   end;
   {$ENDIF}
+  for i:=0 to ComponentCount-1 do begin
+    for j:=0 to ComponentCount-1 do begin
+      if i<>j then
+        TControl(Components[i]).RemoveAllHandlersOfObject(TControl(Components[j]));
+  end;
+  end;
   inherited Destroy;
 end;
 
@@ -3323,6 +3402,7 @@
   HeaderFlatten                    := Settings.HeaderFlatten;
   HeaderFilled                     := Settings.HeaderFilled;
   HeaderHighlightFocused           := Settings.HeaderHighlightFocused;
+  DockSitesCanBeMinimized          := Settings.DockSitesCanBeMinimized;
 end;
 
 procedure TAnchorDockMaster.SaveSettings(Settings: TAnchorDockSettings);
@@ -3343,6 +3423,7 @@
   Settings.HeaderFlatten:=HeaderFlatten;
   Settings.HeaderFilled:=HeaderFilled;
   Settings.HeaderHighlightFocused:=HeaderHighlightFocused;
+  Settings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized;
 end;
 
 function TAnchorDockMaster.SettingsAreEqual(Settings: TAnchorDockSettings
@@ -3680,6 +3761,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -4119,6 +4201,8 @@
 end;
 
 procedure TAnchorDockHostSite.FreePages;
+var
+  i:Integer;
 begin
   FreeAndNil(FPages);
 end;
@@ -4233,6 +4317,14 @@
         akRight: NewBounds.Right:=AControl.Left+AControl.Width;
         akBottom: NewBounds.Bottom:=AControl.Top+AControl.Height;
         end;
+        if (sibling is TAnchorDockHostSite) then
+        if (sibling as TAnchorDockHostSite).FMinimized then begin
+          (sibling as TAnchorDockHostSite).FMinimized:=false;
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Parent:=(sibling as TAnchorDockHostSite);
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Visible:=True;
+          (sibling as TAnchorDockHostSite).FMinimizedControl:=nil;
+          (sibling as TAnchorDockHostSite).UpdateHeaderAlign;
+        end;
         Sibling.BoundsRect:=NewBounds;
       end;
     end;
@@ -4306,6 +4398,13 @@
       FSiteType:=adhstOneControl;
       OnlySiteLeft.Align:=alClient;
       Header.Parent:=Self;
+      if OnlySiteLeft.FMinimized then begin
+        OnlySiteLeft.FMinimized:=false;
+        OnlySiteLeft.FMinimizedControl.Parent:=OnlySiteLeft;
+        OnlySiteLeft.FMinimizedControl.Visible:=True;
+        OnlySiteLeft.FMinimizedControl:=nil;
+        UpdateHeaderAlign;
+      end;
       UpdateHeaderAlign;
 
       //debugln(['TAnchorDockHostSite.RemoveControlFromLayout.ConvertToOneControlType AFTER CONVERT "',Caption,'" to onecontrol OnlySiteLeft="',OnlySiteLeft.Caption,'"']);
@@ -4465,7 +4564,7 @@
     debugln(['TAnchorDockHostSite.Simplify ',DbgSName(Self),' ',DbgSName(AControl)]);
     if AControl is TAnchorDockHostSite then
       SimplifyOneControl
-    else if (AControl=nil) or (csDestroying in AControl.ComponentState) then
+    else if ((AControl=nil) or (csDestroying in AControl.ComponentState)) then
       DockMaster.NeedFree(Self);
   end;
 end;
@@ -4577,7 +4676,8 @@
     Result:=Controls[i];
     if Result.Owner<>Self then exit;
   end;
-  Result:=nil;
+  result:=FMinimizedControl;
+  //Result:=nil;
 end;
 
 function TAnchorDockHostSite.GetSiteCount: integer;
@@ -5165,6 +5265,71 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+begin
+  Application.QueueAsyncCall(@AsyncMinimizeSite,0);
+  //AsyncMinimizeSite,0
+end;
+
+procedure TAnchorDockHostSite.AsyncMinimizeSite(Data: PtrInt);
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  fMinimization:=true;
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  if FMinimized then
+    AControl:=FMinimizedControl
+  else
+    AControl:=GetOneControl;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) or FMinimized then begin
+      FMinimized:=not FMinimized;
+      if FMinimized then begin
+        FMinimizedControl:=AControl;
+        AControl.Visible:=False;
+        AControl.Parent:=nil;
+      end else begin
+        AControl.Parent:=self;
+        AControl.Visible:=True;
+        FMinimizedControl:=nil;
+      end;
+      Splitter.Enabled:=AControl.Visible;
+      UpdateHeaderAlign;
+      Splitter.SetBoundsPercentually;
+    end;
+  end;
+  fMinimization:=false;
+end;
+
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5306,9 +5471,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm))and(Pages=nil);
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5362,9 +5526,33 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+const
+OppositeAlign: array[TAnchorKind] of TAlign = (
+  alBottom, // akTop,
+  alRight,  // akLeft,
+  alLeft,   // akRight,
+  alTop     // akBottom
+  );
+OppositeAnchorKindAlign: array[TAnchorKind] of TADLHeaderPosition = (
+  adlhpBottom, // akTop,
+  adlhpRight,  // akLeft,
+  adlhpLeft,   // akRight,
+  adlhpTop     // akBottom
+  );
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      NeededHeaderPosition:=OppositeAnchorKindAlign[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5390,8 +5578,11 @@
 procedure TAnchorDockHostSite.UpdateHeaderShowing;
 begin
   if Header=nil then exit;
-  if HeaderNeedsShowing then
-    Header.Parent:=Self
+  if HeaderNeedsShowing then begin
+    Header.Parent:=Self;
+    Header.MinimizeButton.Visible:=DockMaster.DockSitesCanBeMinimized;
+    Header.MinimizeButton.Parent:=Header;
+  end
   else
     Header.Parent:=nil;
 end;
@@ -5476,6 +5667,9 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
+  fMinimization:=false;
+  FMinimizedControl:=Nil;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5490,13 +5684,13 @@
 end;
 
 destructor TAnchorDockHostSite.Destroy;
-//var i: Integer;
+var i: Integer;
 begin
-  //debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
-  {for i:=0 to ComponentCount-1 do
+  debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
+  for i:=0 to ComponentCount-1 do
     debugln(['TAnchorDockHostSite.Destroy Component ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   for i:=0 to ControlCount-1 do
-    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);}
+    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);
   FreePages;
   inherited Destroy;
 end;
@@ -5569,6 +5763,13 @@
   end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+begin
+  if Parent is TAnchorDockHostSite then begin
+    TAnchorDockHostSite(Parent).MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5640,6 +5841,13 @@
       r.Right:=CloseButton.Left-1;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+1
+    else
+      r.Right:=MinimizeButton.Left-1;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,7 +5936,14 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
@@ -5742,11 +5957,15 @@
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alTop;
       CloseButton.Align:=alTop;
+    end;
   end else begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alRight;
       CloseButton.Align:=alRight;
+    end;
   end;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
@@ -5787,9 +6006,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,6 +6018,16 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
@@ -5844,6 +6073,44 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMDIMinButtonNormal;
+    if not IsEnabled then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonDisabled{$ELSE}twMDIMinButtonDisabled{$ENDIF}
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonPushed{$ELSE}twMDIMinButtonPushed{$ENDIF}
+    else
+    if FState = bsHot then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonHot{$ELSE}twMDIMinButtonHot{$ENDIF}
+    else
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMDIMinButtonNormal{$ENDIF};
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails({$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF})) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6505,32 +6772,58 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
Index: components/anchordocking/anchordockoptionsdlg.lfm
===================================================================
--- components/anchordocking/anchordockoptionsdlg.lfm	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.lfm	(working copy)
@@ -1,11 +1,13 @@
 object AnchorDockOptionsFrame: TAnchorDockOptionsFrame
   Left = 0
-  Height = 482
+  Height = 567
   Top = 0
-  Width = 416
-  ClientHeight = 482
-  ClientWidth = 416
+  Width = 490
+  ClientHeight = 567
+  ClientWidth = 490
+  DesignTimePPI = 113
   OnClick = FrameClick
+  ParentFont = False
   TabOrder = 0
   DesignLeft = 513
   DesignTop = 189
@@ -12,14 +14,15 @@
   object DragThresholdLabel: TLabel
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
-    Left = 10
-    Height = 13
-    Top = 10
-    Width = 111
-    BorderSpacing.Left = 10
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 12
+    Width = 122
+    BorderSpacing.Left = 12
+    BorderSpacing.Top = 12
     Caption = 'DragThresholdLabel'
     ParentColor = False
+    ParentFont = False
   end
   object DragThresholdTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdLabel
@@ -27,15 +30,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 23
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 31
+    Width = 466
     Max = 20
     OnChange = DragThresholdTrackBarChange
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Right = 10
+    BorderSpacing.Right = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 1
@@ -46,12 +50,13 @@
     AnchorSideTop.Control = DragThresholdLabel
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
-    Left = 127
-    Height = 23
-    Top = 5
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 141
+    Height = 27
+    Top = 8
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 20
+    ParentFont = False
     TabOrder = 0
     Visible = False
   end
@@ -59,13 +64,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = DragThresholdTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 79
-    Width = 103
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 97
+    Width = 112
+    BorderSpacing.Top = 12
     Caption = 'SplitterWidthLabel'
     ParentColor = False
+    ParentFont = False
   end
   object SplitterWidthTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdTrackBar
@@ -73,14 +79,15 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 92
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 116
+    Width = 466
     Min = 1
     OnChange = SplitterWidthTrackBarChange
     Position = 1
     Anchors = [akTop, akLeft, akRight]
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 3
@@ -89,12 +96,13 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = SplitterWidthTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 142
-    Width = 160
-    BorderSpacing.Top = 4
+    Left = 12
+    Height = 23
+    Top = 175
+    Width = 169
+    BorderSpacing.Top = 5
     Caption = 'ScaleOnResizeCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 4
@@ -103,12 +111,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 166
-    Width = 149
+    Left = 12
+    Height = 23
+    Top = 198
+    Width = 160
     Caption = 'ShowHeaderCheckBox'
     OnChange = ShowHeaderCheckBoxChange
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 5
@@ -117,12 +126,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ShowHeaderCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 190
-    Width = 191
-    BorderSpacing.Left = 15
+    Left = 30
+    Height = 23
+    Top = 221
+    Width = 208
+    BorderSpacing.Left = 18
     Caption = 'ShowHeaderCaptionCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 6
@@ -131,11 +141,12 @@
     AnchorSideLeft.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 214
-    Width = 249
+    Left = 30
+    Height = 23
+    Top = 244
+    Width = 272
     Caption = 'HideHeaderCaptionForFloatingCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 7
@@ -147,15 +158,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 122
+    Left = 136
     Height = 27
-    Top = 286
-    Width = 284
+    Top = 313
+    Width = 342
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 6
-    BorderSpacing.Right = 10
-    ItemHeight = 0
+    BorderSpacing.Left = 7
+    BorderSpacing.Right = 12
+    ItemHeight = 19
     OnDrawItem = HeaderStyleComboBoxDrawItem
+    ParentFont = False
     Style = csDropDownList
     TabOrder = 10
   end
@@ -163,23 +175,25 @@
     AnchorSideLeft.Control = ShowHeaderCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrCenter
-    Left = 20
-    Height = 13
-    Top = 293
-    Width = 96
-    BorderSpacing.Left = 10
+    Left = 24
+    Height = 19
+    Top = 317
+    Width = 105
+    BorderSpacing.Left = 12
     Caption = 'HeaderStyleLabel'
     ParentColor = False
+    ParentFont = False
   end
   object FlattenHeadersCheckBox: TCheckBox
     AnchorSideLeft.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 238
-    Width = 164
+    Left = 30
+    Height = 23
+    Top = 267
+    Width = 175
     Caption = 'FlattenHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 8
@@ -188,11 +202,12 @@
     AnchorSideLeft.Control = FlattenHeadersCheckBox
     AnchorSideTop.Control = FlattenHeadersCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 262
-    Width = 154
+    Left = 30
+    Height = 23
+    Top = 290
+    Width = 164
     Caption = 'FilledHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 9
@@ -201,11 +216,12 @@
     AnchorSideLeft.Control = FilledHeadersCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 313
-    Width = 175
+    Left = 30
+    Height = 23
+    Top = 340
+    Width = 189
     Caption = 'HighlightFocusedCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 11
@@ -215,13 +231,14 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = SplitterWidthLabel
     AnchorSideTop.Side = asrCenter
-    Left = 119
-    Height = 23
-    Top = 74
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 131
+    Height = 27
+    Top = 93
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 10
     MinValue = 1
+    ParentFont = False
     TabOrder = 2
     Value = 1
     Visible = False
@@ -228,15 +245,16 @@
   end
   object HeaderAlignTopLabel: TLabel
     AnchorSideLeft.Control = DragThresholdLabel
-    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Control = DockSitesCanBeMinimized
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 347
-    Width = 117
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 398
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignTopLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignTopTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -244,10 +262,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 360
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 417
+    Width = 466
     Frequency = 10
     Max = 150
     OnChange = HeaderAlignTopTrackBarChange
@@ -254,7 +272,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 13
@@ -264,12 +283,13 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignTopLabel
     AnchorSideTop.Side = asrCenter
-    Left = 133
-    Height = 23
-    Top = 342
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 394
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 150
+    ParentFont = False
     TabOrder = 12
     Visible = False
   end
@@ -277,13 +297,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = HeaderAlignTopTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 417
-    Width = 120
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 484
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignLeftLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignLeftTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -291,10 +312,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 430
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 503
+    Width = 466
     Frequency = 10
     Max = 200
     OnChange = HeaderAlignLeftTrackBarChange
@@ -301,7 +322,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 15
@@ -311,13 +333,28 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignLeftLabel
     AnchorSideTop.Side = asrCenter
-    Left = 136
-    Height = 23
-    Top = 412
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 480
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 200
+    ParentFont = False
     TabOrder = 14
     Visible = False
   end
+  object DockSitesCanBeMinimized: TCheckBox
+    AnchorSideLeft.Control = FilledHeadersCheckBox
+    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Side = asrBottom
+    Left = 30
+    Height = 23
+    Top = 363
+    Width = 185
+    Caption = 'DockSitesCanBeMinimized'
+    ParentFont = False
+    ParentShowHint = False
+    ShowHint = True
+    TabOrder = 16
+  end
 end
Index: components/anchordocking/anchordockoptionsdlg.pas
===================================================================
--- components/anchordocking/anchordockoptionsdlg.pas	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.pas	(working copy)
@@ -37,6 +37,7 @@
     HeaderStyleLabel: TLabel;
     HideHeaderCaptionForFloatingCheckBox: TCheckBox;
     HighlightFocusedCheckBox: TCheckBox;
+    DockSitesCanBeMinimized: TCheckBox;
     ScaleOnResizeCheckBox: TCheckBox;
     ShowHeaderCaptionCheckBox: TCheckBox;
     ShowHeaderCheckBox: TCheckBox;
@@ -299,6 +300,7 @@
   HeaderStyleLabel.Enabled:=HasHeaders;
   HeaderStyleComboBox.Enabled:=HasHeaders;
   HighlightFocusedCheckBox.Enabled:=HasHeaders;
+  DockSitesCanBeMinimized.Enabled:=HasHeaders;
 end;
 
 constructor TAnchorDockOptionsFrame.Create(TheOwner: TComponent);
@@ -356,6 +358,7 @@
   TheSettings.HeaderFilled:=FilledHeadersCheckBox.Checked;
   TheSettings.HeaderStyle:=TADHeaderStyle(HeaderStyleComboBox.ItemIndex);
   TheSettings.HeaderHighlightFocused:=HighlightFocusedCheckBox.Checked;
+  TheSettings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized.Checked;
 end;
 
 procedure TAnchorDockOptionsFrame.LoadFromSettings(
@@ -429,6 +432,10 @@
   HighlightFocusedCheckBox.Checked:=TheSettings.HeaderHighlightFocused;
   HighlightFocusedCheckBox.Caption:=adrsHighlightFocused;
   HighlightFocusedCheckBox.Hint:=adrsHighlightFocusedHint;
+
+  DockSitesCanBeMinimized.Checked:=TheSettings.DockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Caption:=adrsDockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Hint:=adrsDockSitesCanBeMinimizedHint;
 end;
 
 end.
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59428)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';
@@ -82,6 +83,8 @@
   adrsFilledHeadersHint = 'Fill headers of docked controls';
   adrsHighlightFocused = 'Highlight focused';
   adrsHighlightFocusedHint = 'Highlight header of focused docked control';
+  adrsDockSitesCanBeMinimized = 'Dock sites can be minimized';
+  adrsDockSitesCanBeMinimizedHint = 'Dock sites can be minimized';
 
 implementation
 

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59428)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -92,9 +92,9 @@
 {$mode objfpc}{$H+}
 
 { $DEFINE VerboseAnchorDockRestore}
-{ $DEFINE VerboseADCustomSite}
-{ $DEFINE VerboseAnchorDockPages}
-{ $DEFINE VerboseAnchorDocking}
+{$DEFINE VerboseADCustomSite}
+{$DEFINE VerboseAnchorDockPages}
+{$DEFINE VerboseAnchorDocking}
 
 interface
 
@@ -123,6 +123,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +141,11 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -154,6 +164,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -262,7 +273,10 @@
     FPages: TAnchorDockPageControl;
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
-    fUpdateLayout: integer;
+    fUpdateLayout: Integer;
+    FMinimized: Boolean;
+    fMinimization: Boolean;
+    FMinimizedControl: TControl;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +333,8 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
+    procedure AsyncMinimizeSite(Data: PtrInt);
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -431,6 +447,7 @@
     FShowHeader: boolean;
     FShowHeaderCaption: boolean;
     FSplitterWidth: integer;
+    FDockSitecCanBeMinimized: boolean;
     procedure SetAllowDragging(AValue: boolean);
     procedure SetDockOutsideMargin(AValue: integer);
     procedure SetDockParentMargin(AValue: integer);
@@ -448,6 +465,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitecCanBeMinimized(AValue: boolean);
   public
     property DragTreshold: integer read FDragTreshold write SetDragTreshold;
     property DockOutsideMargin: integer read FDockOutsideMargin write SetDockOutsideMargin;
@@ -466,6 +484,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused;
+    property DockSitesCanBeMinimized: boolean read FDockSitecCanBeMinimized write SetDockSitecCanBeMinimized;
     procedure IncreaseChangeStamp; inline;
     property ChangeStamp: integer read FChangeStamp;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
@@ -502,6 +521,7 @@
     FHeaderFlatten: boolean;
     FHeaderFilled: boolean;
     FHeaderHighlightFocused: boolean;
+    FDockSitesCanBeMinimized: boolean;
     FIdleConnected: Boolean;
     FManagerClass: TAnchorDockManagerClass;
     FOnCreateControl: TADCreateControlEvent;
@@ -541,6 +561,8 @@
     function GetNodeSite(Node: TAnchorDockLayoutTreeNode): TAnchorDockHostSite;
     procedure MapTreeToControls(Tree: TAnchorDockLayoutTree);
     function RestoreLayout(Tree: TAnchorDockLayoutTree; Scale: boolean): boolean;
+    procedure SetMinimizedState(Tree: TAnchorDockLayoutTree);
+    procedure SetnodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
     procedure EnableAllAutoSizing;
     procedure ClearLayoutProperties(AControl: TControl; NewAlign: TAlign = alClient);
     procedure PopupMenuPopup(Sender: TObject);
@@ -561,6 +583,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitesCanBeMinimized(AValue: boolean);
 
     procedure SetShowMenuItemShowHeader(AValue: boolean);
     procedure SetupSite(Site: TWinControl; ANode: TAnchorDockLayoutTreeNode;
@@ -680,6 +703,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten default true;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled default true;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused default false;
+    property DockSitesCanBeMinimized: boolean read FDockSitesCanBeMinimized write SetDockSitesCanBeMinimized default false;
 
     property SplitterWidth: integer read FSplitterWidth write SetSplitterWidth default 4;
     property ScaleOnResize: boolean read FScaleOnResize write SetScaleOnResize default true; // scale children when resizing a site
@@ -970,6 +994,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -1361,6 +1406,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockSettings.SetDockSitecCanBeMinimized(AValue: boolean);
+begin
+  if FDockSitecCanBeMinimized=AValue then Exit;
+  FDockSitecCanBeMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockSettings.Assign(Source: TAnchorDockSettings);
 begin
   FAllowDragging := Source.FAllowDragging;
@@ -1381,6 +1433,7 @@
   FShowHeaderCaption := Source.FShowHeaderCaption;
   FSplitterWidth := Source.FSplitterWidth;
   FHeaderHighlightFocused:=Source.FHeaderHighlightFocused;
+  FDockSitecCanBeMinimized:=Source.FDockSitecCanBeMinimized;
 end;
 
 procedure TAnchorDockSettings.IncreaseChangeStamp;
@@ -1407,6 +1460,7 @@
   HeaderFlatten:=Config.GetValue('HeaderFlatten',true);
   HeaderFilled:=Config.GetValue('HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue('HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue('DockSitecCanBeMinimized',False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1429,6 +1483,7 @@
   Config.SetDeleteValue(Path+'HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue(Path+'HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue(Path+'HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue(Path+'DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
 end;
 
 procedure TAnchorDockSettings.SaveToConfig(Config: TConfigStorage);
@@ -1450,6 +1505,7 @@
   Config.SetDeleteValue('HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue('HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue('HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue('DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1472,6 +1528,7 @@
       and (HeaderFlatten=Settings.HeaderFlatten)
       and (HeaderFilled=Settings.HeaderFilled)
       and (HeaderHighlightFocused=Settings.HeaderHighlightFocused)
+      and (DockSitesCanBeMinimized=Settings.DockSitesCanBeMinimized)
       ;
 end;
 
@@ -1494,6 +1551,7 @@
   HeaderFlatten:=Config.GetValue(Path+'HeaderFlatten',true);
   HeaderFilled:=Config.GetValue(Path+'HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue(Path+'HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue(Path+'DockSitecCanBeMinimized',False);
 end;
 
 { TAnchorDockMaster }
@@ -2021,6 +2079,8 @@
     aHostSite:=TAnchorDockHostSite(Site);
     aHostSite.Header.HeaderPosition:=ANode.HeaderPosition;
     aHostSite.DockRestoreBounds:=NewBounds;
+    //aHostSite.FMinimized:=ANode.Minimized;
+    //we update aHostSite.FMinimized in TAnchorDockMaster.SetMinimizedState
     if (ANode.NodeType<>adltnPages) and (aHostSite.Pages<>nil) then
       aHostSite.FreePages;
   end;
@@ -2040,6 +2100,25 @@
   fTreeNameToDocker[Node.Name]:=Result;
 end;
 
+procedure TAnchorDockMaster.SetNodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
+var
+  HostSite:TAnchorDockHostSite;
+  i:integer;
+begin
+  HostSite:=GetNodeSite(ANode);
+  if Assigned(HostSite) then
+    if HostSite.FMinimized<>ANode.Minimized then
+      Application.QueueAsyncCall(@HostSite.AsyncMinimizeSite,0);
+      //HostSite.MinimizeSite;
+  for i:=0 to ANode.Count-1 do
+    SetnodeMinimizedState(ANode.Nodes[i]);
+end;
+
+procedure TAnchorDockMaster.SetMinimizedState(Tree: TAnchorDockLayoutTree);
+begin
+  SetnodeMinimizedState(Tree.Root);
+end;
+
 function TAnchorDockMaster.RestoreLayout(Tree: TAnchorDockLayoutTree;
   Scale: boolean): boolean;
 
@@ -2193,7 +2272,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -2358,7 +2437,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -2368,6 +2447,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -2514,6 +2594,24 @@
   InvalidateHeaders;
 end;
 
+procedure TAnchorDockMaster.SetDockSitesCanBeMinimized(AValue: boolean);
+var
+  i:integer;
+  Site: TAnchorDockHostSite;
+begin
+  if FDockSitesCanBeMinimized=AValue then Exit;
+  FDockSitesCanBeMinimized:=AValue;
+  for i:=0 to ComponentCount-1 do begin
+    Site:=TAnchorDockHostSite(Components[i]);
+    if not (Site is TAnchorDockHostSite) then continue;
+    if (Site.Header<>nil) then begin
+      DisableControlAutoSizing(Site);
+      Site.UpdateHeaderShowing;
+    end;
+  end;
+  EnableAllAutoSizing;
+  OptionsChanged;
+end;
 procedure TAnchorDockMaster.SetScaleOnResize(AValue: boolean);
 begin
   if FScaleOnResize=AValue then Exit;
@@ -2698,14 +2796,13 @@
   FPageClass:=TAnchorDockPage;
   FRestoreLayouts:=TAnchorDockRestoreLayouts.Create;
   FHeaderHighlightFocused:=false;
+  FDockSitesCanBeMinimized:=false;
 end;
 
 destructor TAnchorDockMaster.Destroy;
 var
   AControl: TControl;
-  {$IFDEF VerboseAnchorDocking}
-  i: Integer;
-  {$ENDIF}
+  i, j: Integer;
 begin
   QueueSimplify:=false;
   FreeAndNil(FRestoreLayouts);
@@ -2727,6 +2824,12 @@
     debugln(['TAnchorDockMaster.Destroy ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   end;
   {$ENDIF}
+  for i:=0 to ComponentCount-1 do begin
+    for j:=0 to ComponentCount-1 do begin
+      if i<>j then
+        TControl(Components[i]).RemoveAllHandlersOfObject(TControl(Components[j]));
+  end;
+  end;
   inherited Destroy;
 end;
 
@@ -3088,12 +3191,12 @@
   AFormOrDockPanel: TWinControl;
   VisibleControls: TStringList;
 
-  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean);
+  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean; AMinimized:boolean);
   begin
     // custom dock site
     LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
     LayoutNode.NodeType:=adltnCustomSite;
-    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel);
+    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel,AMinimized);
     // can have one normal dock site
     if SaveChildren then
     begin
@@ -3124,7 +3227,7 @@
       debugln(['TAnchorDockMaster.SaveMainLayoutToTree AForm=',DbgSName(AFormOrDockPanel)]);
       DebugWriteChildAnchors(AFormOrDockPanel,true,true);
       if AFormOrDockPanel is TAnchorDockPanel then begin
-        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),{false}true);
+        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),true,false);
         //LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         //TAnchorDockPanel(AFormOrDockPanel).SaveLayout(LayoutTree,LayoutNode);
       end else if AFormOrDockPanel is TAnchorDockHostSite then begin
@@ -3132,12 +3235,12 @@
         LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         Site.SaveLayout(LayoutTree,LayoutNode);
       end else if IsCustomSite(AFormOrDockPanel) then begin
-        SaveFormOrDockPanel(AFormOrDockPanel,true);
+        SaveFormOrDockPanel(AFormOrDockPanel,true,false);
       end else
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    LayoutTree.Root.Simplify(VisibleControls);
+    LayoutTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;
@@ -3157,7 +3260,7 @@
     (AControl as TAnchorDockPanel).SaveLayout(LayoutTree,LayoutTree.Root);
   end else if IsCustomSite(AControl) then begin
     LayoutTree.Root.NodeType:=adltnCustomSite;
-    LayoutTree.Root.Assign(AControl);
+    LayoutTree.Root.Assign(AControl,false,false);
     // can have one normal dock site
     Site:=TAnchorDockManager(AControl.DockManager).GetChildSite;
     if Site<>nil then begin
@@ -3252,7 +3355,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -3262,6 +3365,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -3323,6 +3427,7 @@
   HeaderFlatten                    := Settings.HeaderFlatten;
   HeaderFilled                     := Settings.HeaderFilled;
   HeaderHighlightFocused           := Settings.HeaderHighlightFocused;
+  DockSitesCanBeMinimized          := Settings.DockSitesCanBeMinimized;
 end;
 
 procedure TAnchorDockMaster.SaveSettings(Settings: TAnchorDockSettings);
@@ -3343,6 +3448,7 @@
   Settings.HeaderFlatten:=HeaderFlatten;
   Settings.HeaderFilled:=HeaderFilled;
   Settings.HeaderHighlightFocused:=HeaderHighlightFocused;
+  Settings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized;
 end;
 
 function TAnchorDockMaster.SettingsAreEqual(Settings: TAnchorDockSettings
@@ -3680,6 +3786,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -4119,6 +4226,8 @@
 end;
 
 procedure TAnchorDockHostSite.FreePages;
+var
+  i:Integer;
 begin
   FreeAndNil(FPages);
 end;
@@ -4233,6 +4342,14 @@
         akRight: NewBounds.Right:=AControl.Left+AControl.Width;
         akBottom: NewBounds.Bottom:=AControl.Top+AControl.Height;
         end;
+        if (sibling is TAnchorDockHostSite) then
+        if (sibling as TAnchorDockHostSite).FMinimized then begin
+          (sibling as TAnchorDockHostSite).FMinimized:=false;
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Parent:=(sibling as TAnchorDockHostSite);
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Visible:=True;
+          (sibling as TAnchorDockHostSite).FMinimizedControl:=nil;
+          (sibling as TAnchorDockHostSite).UpdateHeaderAlign;
+        end;
         Sibling.BoundsRect:=NewBounds;
       end;
     end;
@@ -4306,6 +4423,13 @@
       FSiteType:=adhstOneControl;
       OnlySiteLeft.Align:=alClient;
       Header.Parent:=Self;
+      if OnlySiteLeft.FMinimized then begin
+        OnlySiteLeft.FMinimized:=false;
+        OnlySiteLeft.FMinimizedControl.Parent:=OnlySiteLeft;
+        OnlySiteLeft.FMinimizedControl.Visible:=True;
+        OnlySiteLeft.FMinimizedControl:=nil;
+        UpdateHeaderAlign;
+      end;
       UpdateHeaderAlign;
 
       //debugln(['TAnchorDockHostSite.RemoveControlFromLayout.ConvertToOneControlType AFTER CONVERT "',Caption,'" to onecontrol OnlySiteLeft="',OnlySiteLeft.Caption,'"']);
@@ -4465,7 +4589,7 @@
     debugln(['TAnchorDockHostSite.Simplify ',DbgSName(Self),' ',DbgSName(AControl)]);
     if AControl is TAnchorDockHostSite then
       SimplifyOneControl
-    else if (AControl=nil) or (csDestroying in AControl.ComponentState) then
+    else if ((AControl=nil) or (csDestroying in AControl.ComponentState)) then
       DockMaster.NeedFree(Self);
   end;
 end;
@@ -4577,7 +4701,8 @@
     Result:=Controls[i];
     if Result.Owner<>Self then exit;
   end;
-  Result:=nil;
+  result:=FMinimizedControl;
+  //Result:=nil;
 end;
 
 function TAnchorDockHostSite.GetSiteCount: integer;
@@ -5165,6 +5290,71 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+begin
+  //Application.QueueAsyncCall(@AsyncMinimizeSite,0);
+  AsyncMinimizeSite(0);
+end;
+
+procedure TAnchorDockHostSite.AsyncMinimizeSite(Data: PtrInt);
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  fMinimization:=true;
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  if FMinimized then
+    AControl:=FMinimizedControl
+  else
+    AControl:=GetOneControl;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) or FMinimized then begin
+      FMinimized:=not FMinimized;
+      if FMinimized then begin
+        FMinimizedControl:=AControl;
+        AControl.Visible:=False;
+        AControl.Parent:=nil;
+      end else begin
+        AControl.Parent:=self;
+        AControl.Visible:=True;
+        FMinimizedControl:=nil;
+      end;
+      Splitter.Enabled:=AControl.Visible;
+      UpdateHeaderAlign;
+      Splitter.SetBoundsPercentually;
+    end;
+  end;
+  fMinimization:=false;
+end;
+
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5306,9 +5496,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm))and(Pages=nil);
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5362,9 +5551,33 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+const
+OppositeAlign: array[TAnchorKind] of TAlign = (
+  alBottom, // akTop,
+  alRight,  // akLeft,
+  alLeft,   // akRight,
+  alTop     // akBottom
+  );
+OppositeAnchorKindAlign: array[TAnchorKind] of TADLHeaderPosition = (
+  adlhpBottom, // akTop,
+  adlhpRight,  // akLeft,
+  adlhpLeft,   // akRight,
+  adlhpTop     // akBottom
+  );
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      NeededHeaderPosition:=OppositeAnchorKindAlign[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5390,8 +5603,11 @@
 procedure TAnchorDockHostSite.UpdateHeaderShowing;
 begin
   if Header=nil then exit;
-  if HeaderNeedsShowing then
-    Header.Parent:=Self
+  if HeaderNeedsShowing then begin
+    Header.Parent:=Self;
+    Header.MinimizeButton.Visible:=DockMaster.DockSitesCanBeMinimized;
+    Header.MinimizeButton.Parent:=Header;
+  end
   else
     Header.Parent:=nil;
 end;
@@ -5432,7 +5648,7 @@
   if (SiteType=adhstOneControl) and (OneControl<>nil)
   and (not (OneControl is TAnchorDockHostSite)) then begin
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.Name:=OneControl.Name;
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if (SiteType in [adhstLayout,adhstOneControl]) then begin
@@ -5450,7 +5666,7 @@
         Splitter.SaveLayout(ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if SiteType=adhstPages then begin
     LayoutNode.NodeType:=adltnPages;
@@ -5461,7 +5677,7 @@
         Site.SaveLayout(LayoutTree,ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else
     LayoutNode.NodeType:=adltnNone;
@@ -5476,6 +5692,9 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
+  fMinimization:=false;
+  FMinimizedControl:=Nil;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5490,13 +5709,13 @@
 end;
 
 destructor TAnchorDockHostSite.Destroy;
-//var i: Integer;
+var i: Integer;
 begin
-  //debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
-  {for i:=0 to ComponentCount-1 do
+  debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
+  for i:=0 to ComponentCount-1 do
     debugln(['TAnchorDockHostSite.Destroy Component ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   for i:=0 to ControlCount-1 do
-    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);}
+    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);
   FreePages;
   inherited Destroy;
 end;
@@ -5569,6 +5788,13 @@
   end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+begin
+  if Parent is TAnchorDockHostSite then begin
+    TAnchorDockHostSite(Parent).MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5640,6 +5866,13 @@
       r.Right:=CloseButton.Left-1;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+1
+    else
+      r.Right:=MinimizeButton.Left-1;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,7 +5961,14 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
@@ -5742,11 +5982,15 @@
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alTop;
       CloseButton.Align:=alTop;
+    end;
   end else begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alRight;
       CloseButton.Align:=alRight;
+    end;
   end;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
@@ -5787,9 +6031,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,6 +6043,16 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
@@ -5844,6 +6098,44 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMinButtonNormal;
+    if not IsEnabled then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonDisabled{$ELSE}twMinButtonDisabled{$ENDIF}
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonPushed{$ELSE}twMinButtonPushed{$ENDIF}
+    else
+    if FState = bsHot then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonHot{$ELSE}twMinButtonHot{$ENDIF}
+    else
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF};
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails({$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF})) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6505,32 +6797,58 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
@@ -6562,12 +6880,39 @@
 
 procedure TAnchorDockSplitter.SaveLayout(
   LayoutNode: TAnchorDockLayoutTreeNode);
+var
+  NewLeft, NewTop: Integer;
 begin
   if ResizeAnchor in [akLeft,akRight] then
     LayoutNode.NodeType:=adltnSplitterVertical
   else
     LayoutNode.NodeType:=adltnSplitterHorizontal;
-  LayoutNode.Assign(Self);
+  LayoutNode.Assign(Self,false,false);
+
+  if not Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
+    begin
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+      end;
+    end;
+    LayoutNode.BoundsRect:=Rect(NewLeft,NewTop,NewLeft+Width,NewTop+Height);
+  end
 end;
 
 function TAnchorDockSplitter.HasOnlyOneSibling(Side: TAnchorKind; MinPos,
Index: components/anchordocking/anchordockoptionsdlg.lfm
===================================================================
--- components/anchordocking/anchordockoptionsdlg.lfm	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.lfm	(working copy)
@@ -1,11 +1,13 @@
 object AnchorDockOptionsFrame: TAnchorDockOptionsFrame
   Left = 0
-  Height = 482
+  Height = 567
   Top = 0
-  Width = 416
-  ClientHeight = 482
-  ClientWidth = 416
+  Width = 490
+  ClientHeight = 567
+  ClientWidth = 490
+  DesignTimePPI = 113
   OnClick = FrameClick
+  ParentFont = False
   TabOrder = 0
   DesignLeft = 513
   DesignTop = 189
@@ -12,14 +14,15 @@
   object DragThresholdLabel: TLabel
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
-    Left = 10
-    Height = 13
-    Top = 10
-    Width = 111
-    BorderSpacing.Left = 10
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 12
+    Width = 122
+    BorderSpacing.Left = 12
+    BorderSpacing.Top = 12
     Caption = 'DragThresholdLabel'
     ParentColor = False
+    ParentFont = False
   end
   object DragThresholdTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdLabel
@@ -27,15 +30,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 23
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 31
+    Width = 466
     Max = 20
     OnChange = DragThresholdTrackBarChange
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Right = 10
+    BorderSpacing.Right = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 1
@@ -46,12 +50,13 @@
     AnchorSideTop.Control = DragThresholdLabel
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
-    Left = 127
-    Height = 23
-    Top = 5
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 141
+    Height = 27
+    Top = 8
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 20
+    ParentFont = False
     TabOrder = 0
     Visible = False
   end
@@ -59,13 +64,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = DragThresholdTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 79
-    Width = 103
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 97
+    Width = 112
+    BorderSpacing.Top = 12
     Caption = 'SplitterWidthLabel'
     ParentColor = False
+    ParentFont = False
   end
   object SplitterWidthTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdTrackBar
@@ -73,14 +79,15 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 92
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 116
+    Width = 466
     Min = 1
     OnChange = SplitterWidthTrackBarChange
     Position = 1
     Anchors = [akTop, akLeft, akRight]
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 3
@@ -89,12 +96,13 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = SplitterWidthTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 142
-    Width = 160
-    BorderSpacing.Top = 4
+    Left = 12
+    Height = 23
+    Top = 175
+    Width = 169
+    BorderSpacing.Top = 5
     Caption = 'ScaleOnResizeCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 4
@@ -103,12 +111,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 166
-    Width = 149
+    Left = 12
+    Height = 23
+    Top = 198
+    Width = 160
     Caption = 'ShowHeaderCheckBox'
     OnChange = ShowHeaderCheckBoxChange
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 5
@@ -117,12 +126,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ShowHeaderCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 190
-    Width = 191
-    BorderSpacing.Left = 15
+    Left = 30
+    Height = 23
+    Top = 221
+    Width = 208
+    BorderSpacing.Left = 18
     Caption = 'ShowHeaderCaptionCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 6
@@ -131,11 +141,12 @@
     AnchorSideLeft.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 214
-    Width = 249
+    Left = 30
+    Height = 23
+    Top = 244
+    Width = 272
     Caption = 'HideHeaderCaptionForFloatingCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 7
@@ -147,15 +158,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 122
+    Left = 136
     Height = 27
-    Top = 286
-    Width = 284
+    Top = 313
+    Width = 342
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 6
-    BorderSpacing.Right = 10
-    ItemHeight = 0
+    BorderSpacing.Left = 7
+    BorderSpacing.Right = 12
+    ItemHeight = 19
     OnDrawItem = HeaderStyleComboBoxDrawItem
+    ParentFont = False
     Style = csDropDownList
     TabOrder = 10
   end
@@ -163,23 +175,25 @@
     AnchorSideLeft.Control = ShowHeaderCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrCenter
-    Left = 20
-    Height = 13
-    Top = 293
-    Width = 96
-    BorderSpacing.Left = 10
+    Left = 24
+    Height = 19
+    Top = 317
+    Width = 105
+    BorderSpacing.Left = 12
     Caption = 'HeaderStyleLabel'
     ParentColor = False
+    ParentFont = False
   end
   object FlattenHeadersCheckBox: TCheckBox
     AnchorSideLeft.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 238
-    Width = 164
+    Left = 30
+    Height = 23
+    Top = 267
+    Width = 175
     Caption = 'FlattenHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 8
@@ -188,11 +202,12 @@
     AnchorSideLeft.Control = FlattenHeadersCheckBox
     AnchorSideTop.Control = FlattenHeadersCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 262
-    Width = 154
+    Left = 30
+    Height = 23
+    Top = 290
+    Width = 164
     Caption = 'FilledHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 9
@@ -201,11 +216,12 @@
     AnchorSideLeft.Control = FilledHeadersCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 313
-    Width = 175
+    Left = 30
+    Height = 23
+    Top = 340
+    Width = 189
     Caption = 'HighlightFocusedCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 11
@@ -215,13 +231,14 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = SplitterWidthLabel
     AnchorSideTop.Side = asrCenter
-    Left = 119
-    Height = 23
-    Top = 74
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 131
+    Height = 27
+    Top = 93
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 10
     MinValue = 1
+    ParentFont = False
     TabOrder = 2
     Value = 1
     Visible = False
@@ -228,15 +245,16 @@
   end
   object HeaderAlignTopLabel: TLabel
     AnchorSideLeft.Control = DragThresholdLabel
-    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Control = DockSitesCanBeMinimized
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 347
-    Width = 117
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 398
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignTopLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignTopTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -244,10 +262,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 360
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 417
+    Width = 466
     Frequency = 10
     Max = 150
     OnChange = HeaderAlignTopTrackBarChange
@@ -254,7 +272,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 13
@@ -264,12 +283,13 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignTopLabel
     AnchorSideTop.Side = asrCenter
-    Left = 133
-    Height = 23
-    Top = 342
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 394
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 150
+    ParentFont = False
     TabOrder = 12
     Visible = False
   end
@@ -277,13 +297,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = HeaderAlignTopTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 417
-    Width = 120
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 484
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignLeftLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignLeftTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -291,10 +312,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 430
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 503
+    Width = 466
     Frequency = 10
     Max = 200
     OnChange = HeaderAlignLeftTrackBarChange
@@ -301,7 +322,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 15
@@ -311,13 +333,28 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignLeftLabel
     AnchorSideTop.Side = asrCenter
-    Left = 136
-    Height = 23
-    Top = 412
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 480
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 200
+    ParentFont = False
     TabOrder = 14
     Visible = False
   end
+  object DockSitesCanBeMinimized: TCheckBox
+    AnchorSideLeft.Control = FilledHeadersCheckBox
+    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Side = asrBottom
+    Left = 30
+    Height = 23
+    Top = 363
+    Width = 185
+    Caption = 'DockSitesCanBeMinimized'
+    ParentFont = False
+    ParentShowHint = False
+    ShowHint = True
+    TabOrder = 16
+  end
 end
Index: components/anchordocking/anchordockoptionsdlg.pas
===================================================================
--- components/anchordocking/anchordockoptionsdlg.pas	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.pas	(working copy)
@@ -37,6 +37,7 @@
     HeaderStyleLabel: TLabel;
     HideHeaderCaptionForFloatingCheckBox: TCheckBox;
     HighlightFocusedCheckBox: TCheckBox;
+    DockSitesCanBeMinimized: TCheckBox;
     ScaleOnResizeCheckBox: TCheckBox;
     ShowHeaderCaptionCheckBox: TCheckBox;
     ShowHeaderCheckBox: TCheckBox;
@@ -299,6 +300,7 @@
   HeaderStyleLabel.Enabled:=HasHeaders;
   HeaderStyleComboBox.Enabled:=HasHeaders;
   HighlightFocusedCheckBox.Enabled:=HasHeaders;
+  DockSitesCanBeMinimized.Enabled:=HasHeaders;
 end;
 
 constructor TAnchorDockOptionsFrame.Create(TheOwner: TComponent);
@@ -356,6 +358,7 @@
   TheSettings.HeaderFilled:=FilledHeadersCheckBox.Checked;
   TheSettings.HeaderStyle:=TADHeaderStyle(HeaderStyleComboBox.ItemIndex);
   TheSettings.HeaderHighlightFocused:=HighlightFocusedCheckBox.Checked;
+  TheSettings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized.Checked;
 end;
 
 procedure TAnchorDockOptionsFrame.LoadFromSettings(
@@ -429,6 +432,10 @@
   HighlightFocusedCheckBox.Checked:=TheSettings.HeaderHighlightFocused;
   HighlightFocusedCheckBox.Caption:=adrsHighlightFocused;
   HighlightFocusedCheckBox.Hint:=adrsHighlightFocusedHint;
+
+  DockSitesCanBeMinimized.Checked:=TheSettings.DockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Caption:=adrsDockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Hint:=adrsDockSitesCanBeMinimizedHint;
 end;
 
 end.
Index: components/anchordocking/anchordockpanel.pas
===================================================================
--- components/anchordocking/anchordockpanel.pas	(revision 59428)
+++ components/anchordocking/anchordockpanel.pas	(working copy)
@@ -55,7 +55,7 @@
   begin
 
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,false);
     LayoutNode.Name:={OneControl.}Name;
 
     TAnchorDockHostSite(OneControl).SaveLayout(LayoutTree,LayoutNode);
Index: components/anchordocking/anchordockstorage.pas
===================================================================
--- components/anchordocking/anchordockstorage.pas	(revision 59428)
+++ components/anchordocking/anchordockstorage.pas	(working copy)
@@ -64,6 +64,7 @@
     FTabPosition: TTabPosition;
     FWindowState: TWindowState;
     FControlLocation: TADLControlLocation;
+    FMinimized: Boolean;
     function GetAnchors(Site: TAnchorKind): string;
     function GetBottom: integer;
     function GetHeight: integer;
@@ -90,6 +91,7 @@
     procedure SetTop(const AValue: integer);
     procedure SetWidth(const AValue: integer);
     procedure SetWindowState(const AValue: TWindowState);
+    procedure SetMinimized(const AValue: boolean);
   public
     constructor Create;
     destructor Destroy; override;
@@ -96,7 +98,7 @@
     procedure Clear;
     function IsEqual(Node: TAnchorDockLayoutTreeNode): boolean;
     procedure Assign(Node: TAnchorDockLayoutTreeNode); overload;
-    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean=false); overload;
+    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean); overload;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
     procedure LoadFromConfig(Path: string; Config: TRttiXMLConfig); overload;
     procedure SaveToConfig(Config: TConfigStorage); overload;
@@ -106,7 +108,7 @@
     procedure CheckConsistency; virtual;
 
     // simplifying
-    procedure Simplify(ExistingNames: TStrings);
+    procedure Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
     procedure DeleteNode(ChildNode: TAnchorDockLayoutTreeNode);
     function FindNodeBoundSplitter(ChildNode: TAnchorDockLayoutTreeNode;
                                    Side: TAnchorKind): TAnchorDockLayoutTreeNode;
@@ -135,6 +137,7 @@
     property Monitor: integer read FMonitor write SetMonitor;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property TabPosition: TTabPosition read FTabPosition write SetTabPosition;
+    property Minimized: Boolean read FMinimized write SetMinimized;
     function Count: integer;
     function IsSplitter: boolean;
     function IsRootWindow: boolean;
@@ -988,6 +991,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockLayoutTreeNode.SetMinimized(const AValue: boolean);
+begin
+  if FMinimized=AValue then exit;
+  FMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockLayoutTreeNode.SetTop(const AValue: integer);
 begin
   if Top=AValue then exit;
@@ -1084,6 +1094,7 @@
   BoundSplitterPos:=Node.BoundSplitterPos;
   WorkAreaRect:=Node.WorkAreaRect;
   Monitor:=Node.Monitor;
+  Minimized:=Node.Minimized;
   for a:=low(TAnchorKind) to high(TAnchorKind) do
     Anchors[a]:=Node.Anchors[a];
   while Count>Node.Count do Nodes[Count-1].Free;
@@ -1098,9 +1109,10 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean=false);
+procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean);
 var
   AnchorControl: TControl;
+  ParentForm:TCustomForm;
   a: TAnchorKind;
 begin
   Name:=AControl.Name;
@@ -1109,12 +1121,18 @@
   else
     BoundsRect:=AControl.BoundsRect;
   Align:=AControl.Align;
+  Minimized:=AMinimized;
   if (AControl.Parent=nil) and (AControl is TCustomForm) then begin
     WindowState:=TCustomForm(AControl).WindowState;
     Monitor:=TCustomForm(AControl).Monitor.MonitorNum;
     WorkAreaRect:=TCustomForm(AControl).Monitor.WorkareaRect;
-  end else
-    WindowState:=GetParentForm(AControl).WindowState;
+  end else begin
+    ParentForm:=GetParentForm(AControl);
+    if assigned(ParentForm) then
+      WindowState:=ParentForm.WindowState
+    else
+      WindowState:=wsNormal;
+  end;
   if AControl is TCustomTabControl then
     TabPosition:=TCustomTabControl(AControl).TabPosition
   else
@@ -1137,6 +1155,7 @@
   Clear;
   Name:=Config.GetValue('Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue('Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue('Minimized',false);
   Left:=Config.GetValue('Bounds/Left',0);
   Top:=Config.GetValue('Bounds/Top',0);
   Width:=Config.GetValue('Bounds/Width',0);
@@ -1171,6 +1190,7 @@
   Clear;
   Name:=Config.GetValue(Path+'Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue(Path+'Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue(Path+'Minimized',false);
   Left:=Config.GetValue(Path+'Bounds/Left',0);
   Top:=Config.GetValue(Path+'Bounds/Top',0);
   Width:=Config.GetValue(Path+'Bounds/Width',0);
@@ -1219,6 +1239,7 @@
                                           ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue('Header/TabPosition',ADLTabPostionNames[TabPosition],
                                              ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue('Minimized',Minimized,False);
   Config.SetDeleteValue('Monitor',Monitor,0);
   Config.SetDeleteValue('ChildCount',Count,0);
   for i:=1 to Count do begin
@@ -1252,6 +1273,7 @@
                                                ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue(Path+'Header/TabPosition',ADLTabPostionNames[TabPosition],
                                                   ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue(Path+'Minimized',Minimized,False);
   Config.SetDeleteValue(Path+'Monitor',Monitor,0);
   Config.SetDeleteValue(Path+'ChildCount',Count,0);
   for i:=1 to Count do
@@ -1397,7 +1419,7 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings);
+procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
 { Simplification rules:
    1. Control nodes without existing name are deleted.
    2. Empty layouts and pages are deleted
@@ -1406,16 +1428,18 @@
 var
   i: Integer;
   ChildNode: TAnchorDockLayoutTreeNode;
+  NodeMinimized:boolean;
 begin
   // simplify children
   i:=Count-1;
   while i>=0 do begin
     ChildNode:=Nodes[i];
-    ChildNode.Simplify(ExistingNames);
+    NodeMinimized:=ParentMinimized or ChildNode.Minimized;
+    ChildNode.Simplify(ExistingNames,NodeMinimized);
 
     if (ChildNode.NodeType=adltnControl) then begin
       // leaf node => check if there is a control
-      if (ChildNode.Name='') or (ExistingNames.IndexOf(ChildNode.Name)<0) then
+      if (ChildNode.Name='') or ((ExistingNames.IndexOf(ChildNode.Name)<0) and (not NodeMinimized)) then
         DeleteNode(ChildNode);
     end else if ChildNode.IsSplitter then begin
       // splitter
@@ -1424,7 +1448,7 @@
         ChildNode[0].Free;
     end else if ChildNode.NodeType=adltnCustomSite then begin
       // custom dock site
-    end else if ChildNode.Count=0 then begin
+    end else if (ChildNode.Count=0)and(not NodeMinimized) then begin
       // inner node without child => delete
       DeleteNode(ChildNode);
     end else if (ChildNode.Count=1)
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59428)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';
@@ -82,6 +83,8 @@
   adrsFilledHeadersHint = 'Fill headers of docked controls';
   adrsHighlightFocused = 'Highlight focused';
   adrsHighlightFocusedHint = 'Highlight header of focused docked control';
+  adrsDockSitesCanBeMinimized = 'Dock sites can be minimized';
+  adrsDockSitesCanBeMinimizedHint = 'Dock sites can be minimized';
 
 implementation
 
Index: components/anchordocking/design/anchordesktopoptions.pas
===================================================================
--- components/anchordocking/design/anchordesktopoptions.pas	(revision 59428)
+++ components/anchordocking/design/anchordesktopoptions.pas	(working copy)
@@ -272,7 +272,7 @@
         // custom dock site
         LayoutNode:=FTree.NewNode(FTree.Root);
         LayoutNode.NodeType:=adltnCustomSite;
-        LayoutNode.Assign(AForm);
+        LayoutNode.Assign(AForm,false,false);
         // can have one normal dock site
         Site:=TAnchorDockManager(AForm.DockManager).GetChildSite;
         if Site<>nil then begin
@@ -287,7 +287,7 @@
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    FTree.Root.Simplify(VisibleControls);
+    FTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59428)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -92,9 +92,9 @@
 {$mode objfpc}{$H+}
 
 { $DEFINE VerboseAnchorDockRestore}
-{ $DEFINE VerboseADCustomSite}
-{ $DEFINE VerboseAnchorDockPages}
-{ $DEFINE VerboseAnchorDocking}
+{$DEFINE VerboseADCustomSite}
+{$DEFINE VerboseAnchorDockPages}
+{$DEFINE VerboseAnchorDocking}
 
 interface
 
@@ -109,6 +109,10 @@
 const ADAutoSizingReason = 'TAnchorDockMaster Delayed';
 {$ENDIF}
 
+const EmptyMouseTimeStartX=low(Integer);
+      MouseNoMoveDelta=5;
+      MouseNoMoveTime=500;
+
 type
   TAnchorDockHostSite = class;
 
@@ -123,6 +127,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +145,12 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
+    FMouseTimeStartX,FMouseTimeStartY:Integer;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -147,6 +162,11 @@
           PreferredHeight: integer; WithThemeSpace: Boolean); override;
     procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X,
              Y: Integer); override;
+    procedure MouseMove(Shift: TShiftState; X,Y: Integer); override;
+    procedure MouseLeave;  override;
+    procedure StartMouseNoMoveTimer(X, Y: Integer);
+    procedure StopMouseNoMoveTimer;
+    procedure DoMouseNoMoveTimer(Sender: TObject);
     procedure UpdateHeaderControls;
     procedure SetAlign(Value: TAlign); override;
     procedure DoOnShowHint(HintInfo: PHintInfo); override;
@@ -154,6 +174,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -190,6 +211,7 @@
     procedure SetBoundsKeepDockBounds(ALeft, ATop, AWidth, AHeight: integer); // movement for scaling keeps the DockBounds
     function SideAnchoredControlCount(Side: TAnchorKind): integer;
     function HasAnchoredControls: boolean;
+    function GetSpliterBoundsWithUnminimizedDockSites:TRect;
     procedure SaveLayout(LayoutNode: TAnchorDockLayoutTreeNode);
     function HasOnlyOneSibling(Side: TAnchorKind; MinPos, MaxPos: integer): TControl;
     property DockRestoreBounds: TRect read FDockRestoreBounds write FDockRestoreBounds;
@@ -241,6 +263,15 @@
   end;
   TAnchorDockPageControlClass = class of TAnchorDockPageControl;
 
+
+  TAnchorDockOverlappingForm = class(TCustomForm)
+  protected
+    procedure MouseLeave;  override;
+  public
+    AnchorDockHostSite:TAnchorDockHostSite;
+    constructor CreateNew(AOwner: TComponent; Num: Integer = 0); override;
+  end;
+
   { TAnchorDockHostSite
     This form is the dockhostsite for all controls.
     When docked together they build a tree structure with the docked controls
@@ -262,7 +293,11 @@
     FPages: TAnchorDockPageControl;
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
-    fUpdateLayout: integer;
+    fUpdateLayout: Integer;
+    FMinimized: Boolean;
+    fMinimization: Boolean;
+    FMinimizedControl: TControl;
+    //OverlappingForm:TAnchorDockOverlappingForm;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +354,10 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
+    procedure AsyncMinimizeSite(Data: PtrInt);
+    procedure ShowMinimizedControl;
+    procedure HideMinimizedControl;
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -431,6 +470,7 @@
     FShowHeader: boolean;
     FShowHeaderCaption: boolean;
     FSplitterWidth: integer;
+    FDockSitecCanBeMinimized: boolean;
     procedure SetAllowDragging(AValue: boolean);
     procedure SetDockOutsideMargin(AValue: integer);
     procedure SetDockParentMargin(AValue: integer);
@@ -448,6 +488,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitecCanBeMinimized(AValue: boolean);
   public
     property DragTreshold: integer read FDragTreshold write SetDragTreshold;
     property DockOutsideMargin: integer read FDockOutsideMargin write SetDockOutsideMargin;
@@ -466,6 +507,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused;
+    property DockSitesCanBeMinimized: boolean read FDockSitecCanBeMinimized write SetDockSitecCanBeMinimized;
     procedure IncreaseChangeStamp; inline;
     property ChangeStamp: integer read FChangeStamp;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
@@ -502,6 +544,7 @@
     FHeaderFlatten: boolean;
     FHeaderFilled: boolean;
     FHeaderHighlightFocused: boolean;
+    FDockSitesCanBeMinimized: boolean;
     FIdleConnected: Boolean;
     FManagerClass: TAnchorDockManagerClass;
     FOnCreateControl: TADCreateControlEvent;
@@ -531,6 +574,7 @@
     fPopupMenu: TPopupMenu;
     // Used by RestoreLayout:
     WorkArea, SrcWorkArea: TRect;
+    FOverlappingForm:TAnchorDockOverlappingForm;
 
     function GetControls(Index: integer): TControl;
     function GetLocalizedHeaderHint: string;
@@ -541,6 +585,8 @@
     function GetNodeSite(Node: TAnchorDockLayoutTreeNode): TAnchorDockHostSite;
     procedure MapTreeToControls(Tree: TAnchorDockLayoutTree);
     function RestoreLayout(Tree: TAnchorDockLayoutTree; Scale: boolean): boolean;
+    procedure SetMinimizedState(Tree: TAnchorDockLayoutTree);
+    procedure SetnodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
     procedure EnableAllAutoSizing;
     procedure ClearLayoutProperties(AControl: TControl; NewAlign: TAlign = alClient);
     procedure PopupMenuPopup(Sender: TObject);
@@ -561,6 +607,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitesCanBeMinimized(AValue: boolean);
 
     procedure SetShowMenuItemShowHeader(AValue: boolean);
     procedure SetupSite(Site: TWinControl; ANode: TAnchorDockLayoutTreeNode;
@@ -586,6 +633,8 @@
     procedure OnIdle(Sender: TObject; var Done: Boolean);
     procedure AsyncSimplify({%H-}Data: PtrInt);
   public
+    procedure ShowOverlappingForm;
+    procedure HideOverlappingForm;
     constructor Create(AOwner: TComponent); override;
     destructor Destroy; override;
     function FullRestoreLayout(Tree: TAnchorDockLayoutTree; Scale: Boolean): Boolean;
@@ -680,6 +729,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten default true;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled default true;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused default false;
+    property DockSitesCanBeMinimized: boolean read FDockSitesCanBeMinimized write SetDockSitesCanBeMinimized default false;
 
     property SplitterWidth: integer read FSplitterWidth write SetSplitterWidth default 4;
     property ScaleOnResize: boolean read FScaleOnResize write SetScaleOnResize default true; // scale children when resizing a site
@@ -698,6 +748,7 @@
 
 var
   DockMaster: TAnchorDockMaster = nil;
+  MouseNoMoveTimer: TTimer = nil;
 
 const
   ADHeaderStyleNames: array[TADHeaderStyle] of string = (
@@ -970,6 +1021,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -1361,6 +1433,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockSettings.SetDockSitecCanBeMinimized(AValue: boolean);
+begin
+  if FDockSitecCanBeMinimized=AValue then Exit;
+  FDockSitecCanBeMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockSettings.Assign(Source: TAnchorDockSettings);
 begin
   FAllowDragging := Source.FAllowDragging;
@@ -1381,6 +1460,7 @@
   FShowHeaderCaption := Source.FShowHeaderCaption;
   FSplitterWidth := Source.FSplitterWidth;
   FHeaderHighlightFocused:=Source.FHeaderHighlightFocused;
+  FDockSitecCanBeMinimized:=Source.FDockSitecCanBeMinimized;
 end;
 
 procedure TAnchorDockSettings.IncreaseChangeStamp;
@@ -1407,6 +1487,7 @@
   HeaderFlatten:=Config.GetValue('HeaderFlatten',true);
   HeaderFilled:=Config.GetValue('HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue('HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue('DockSitecCanBeMinimized',False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1429,6 +1510,7 @@
   Config.SetDeleteValue(Path+'HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue(Path+'HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue(Path+'HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue(Path+'DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
 end;
 
 procedure TAnchorDockSettings.SaveToConfig(Config: TConfigStorage);
@@ -1450,6 +1532,7 @@
   Config.SetDeleteValue('HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue('HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue('HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue('DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1472,6 +1555,7 @@
       and (HeaderFlatten=Settings.HeaderFlatten)
       and (HeaderFilled=Settings.HeaderFilled)
       and (HeaderHighlightFocused=Settings.HeaderHighlightFocused)
+      and (DockSitesCanBeMinimized=Settings.DockSitesCanBeMinimized)
       ;
 end;
 
@@ -1494,6 +1578,7 @@
   HeaderFlatten:=Config.GetValue(Path+'HeaderFlatten',true);
   HeaderFilled:=Config.GetValue(Path+'HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue(Path+'HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue(Path+'DockSitecCanBeMinimized',False);
 end;
 
 { TAnchorDockMaster }
@@ -2021,6 +2106,8 @@
     aHostSite:=TAnchorDockHostSite(Site);
     aHostSite.Header.HeaderPosition:=ANode.HeaderPosition;
     aHostSite.DockRestoreBounds:=NewBounds;
+    //aHostSite.FMinimized:=ANode.Minimized;
+    //we update aHostSite.FMinimized in TAnchorDockMaster.SetMinimizedState
     if (ANode.NodeType<>adltnPages) and (aHostSite.Pages<>nil) then
       aHostSite.FreePages;
   end;
@@ -2040,6 +2127,25 @@
   fTreeNameToDocker[Node.Name]:=Result;
 end;
 
+procedure TAnchorDockMaster.SetNodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
+var
+  HostSite:TAnchorDockHostSite;
+  i:integer;
+begin
+  HostSite:=GetNodeSite(ANode);
+  if Assigned(HostSite) then
+    if HostSite.FMinimized<>ANode.Minimized then
+      Application.QueueAsyncCall(@HostSite.AsyncMinimizeSite,0);
+      //HostSite.MinimizeSite;
+  for i:=0 to ANode.Count-1 do
+    SetnodeMinimizedState(ANode.Nodes[i]);
+end;
+
+procedure TAnchorDockMaster.SetMinimizedState(Tree: TAnchorDockLayoutTree);
+begin
+  SetnodeMinimizedState(Tree.Root);
+end;
+
 function TAnchorDockMaster.RestoreLayout(Tree: TAnchorDockLayoutTree;
   Scale: boolean): boolean;
 
@@ -2193,7 +2299,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -2358,7 +2464,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -2368,6 +2474,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -2423,10 +2530,22 @@
 end;
 
 procedure TAnchorDockMaster.OnIdle(Sender: TObject; var Done: Boolean);
+var
+  MousePos: TPoint;
+  Bounds:Trect;
 begin
   if Done then ;
-  IdleConnected:=false;
   Restoring:=false;
+  if FOverlappingForm=nil then
+    IdleConnected:=false
+  else begin
+    GetCursorPos(MousePos);
+    Bounds.TopLeft:=FOverlappingForm.ClientToScreen(point(0,0));
+    Bounds.BottomRight:=FOverlappingForm.ClientToScreen(point(FOverlappingForm.Width,FOverlappingForm.Height));
+    if not PtInRect(Bounds,MousePos) then begin
+      HideOverlappingForm;
+    end;
+  end;
 end;
 
 procedure TAnchorDockMaster.AsyncSimplify(Data: PtrInt);
@@ -2514,6 +2633,24 @@
   InvalidateHeaders;
 end;
 
+procedure TAnchorDockMaster.SetDockSitesCanBeMinimized(AValue: boolean);
+var
+  i:integer;
+  Site: TAnchorDockHostSite;
+begin
+  if FDockSitesCanBeMinimized=AValue then Exit;
+  FDockSitesCanBeMinimized:=AValue;
+  for i:=0 to ComponentCount-1 do begin
+    Site:=TAnchorDockHostSite(Components[i]);
+    if not (Site is TAnchorDockHostSite) then continue;
+    if (Site.Header<>nil) then begin
+      DisableControlAutoSizing(Site);
+      Site.UpdateHeaderShowing;
+    end;
+  end;
+  EnableAllAutoSizing;
+  OptionsChanged;
+end;
 procedure TAnchorDockMaster.SetScaleOnResize(AValue: boolean);
 begin
   if FScaleOnResize=AValue then Exit;
@@ -2668,6 +2805,19 @@
     EnableAllAutoSizing;
 end;
 
+procedure TAnchorDockMaster.ShowOverlappingForm;
+begin
+  FOverlappingForm.Show;
+  IdleConnected:=true;
+end;
+
+procedure TAnchorDockMaster.HideOverlappingForm;
+begin
+  FOverlappingForm.Hide;
+  FOverlappingForm.AnchorDockHostSite.HideMinimizedControl;
+  IdleConnected:=false;
+end;
+
 constructor TAnchorDockMaster.Create(AOwner: TComponent);
 begin
   inherited Create(AOwner);
@@ -2698,14 +2848,14 @@
   FPageClass:=TAnchorDockPage;
   FRestoreLayouts:=TAnchorDockRestoreLayouts.Create;
   FHeaderHighlightFocused:=false;
+  FDockSitesCanBeMinimized:=false;
+  FOverlappingForm:=nil;
 end;
 
 destructor TAnchorDockMaster.Destroy;
 var
   AControl: TControl;
-  {$IFDEF VerboseAnchorDocking}
-  i: Integer;
-  {$ENDIF}
+  i, j: Integer;
 begin
   QueueSimplify:=false;
   FreeAndNil(FRestoreLayouts);
@@ -2727,6 +2877,12 @@
     debugln(['TAnchorDockMaster.Destroy ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   end;
   {$ENDIF}
+  for i:=0 to ComponentCount-1 do begin
+    for j:=0 to ComponentCount-1 do begin
+      if i<>j then
+        TControl(Components[i]).RemoveAllHandlersOfObject(TControl(Components[j]));
+  end;
+  end;
   inherited Destroy;
 end;
 
@@ -3018,7 +3174,8 @@
   i:=Screen.CustomFormCount-1;
   while i>=0 do begin
     AForm:=GetParentForm(Screen.CustomForms[i]);
-    AForm.Hide;
+    if Assigned(AForm)then
+      AForm.Hide;
     i:=Min(i,Screen.CustomFormCount)-1;
   end;
 
@@ -3062,8 +3219,11 @@
   end;
 end;
 
-function GetParentFormOrDockPanel(Control: TControl): TCustomForm;
+function GetParentFormOrDockPanel(Control: TControl; TopForm:Boolean=true): TCustomForm;
+var
+  oldControl: TControl;
 begin
+  oldControl:=Control;
   while (Control <> nil) and (Control.Parent <> nil) do
   begin
     if (Control is TAnchorDockPanel) then
@@ -3076,6 +3236,18 @@
     Result := TCustomForm(Control)
   else
     Result := nil;
+  if not TopForm then begin
+    if Control is TAnchorDockPanel then
+      exit;
+    Control:=oldControl;
+    while (Control <> nil) and (Control.Parent <> nil) do
+    begin
+      Control := Control.Parent;
+      if (Control is TCustomForm) then
+        Break;
+    end;
+    Result := TCustomForm(Control);
+  end;
 end;
 
 procedure TAnchorDockMaster.SaveMainLayoutToTree(LayoutTree: TAnchorDockLayoutTree);
@@ -3088,12 +3260,12 @@
   AFormOrDockPanel: TWinControl;
   VisibleControls: TStringList;
 
-  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean);
+  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean; AMinimized:boolean);
   begin
     // custom dock site
     LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
     LayoutNode.NodeType:=adltnCustomSite;
-    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel);
+    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel,AMinimized);
     // can have one normal dock site
     if SaveChildren then
     begin
@@ -3124,7 +3296,7 @@
       debugln(['TAnchorDockMaster.SaveMainLayoutToTree AForm=',DbgSName(AFormOrDockPanel)]);
       DebugWriteChildAnchors(AFormOrDockPanel,true,true);
       if AFormOrDockPanel is TAnchorDockPanel then begin
-        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),{false}true);
+        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),true,false);
         //LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         //TAnchorDockPanel(AFormOrDockPanel).SaveLayout(LayoutTree,LayoutNode);
       end else if AFormOrDockPanel is TAnchorDockHostSite then begin
@@ -3132,12 +3304,12 @@
         LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         Site.SaveLayout(LayoutTree,LayoutNode);
       end else if IsCustomSite(AFormOrDockPanel) then begin
-        SaveFormOrDockPanel(AFormOrDockPanel,true);
+        SaveFormOrDockPanel(AFormOrDockPanel,true,false);
       end else
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    LayoutTree.Root.Simplify(VisibleControls);
+    LayoutTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;
@@ -3157,7 +3329,7 @@
     (AControl as TAnchorDockPanel).SaveLayout(LayoutTree,LayoutTree.Root);
   end else if IsCustomSite(AControl) then begin
     LayoutTree.Root.NodeType:=adltnCustomSite;
-    LayoutTree.Root.Assign(AControl);
+    LayoutTree.Root.Assign(AControl,false,false);
     // can have one normal dock site
     Site:=TAnchorDockManager(AControl.DockManager).GetChildSite;
     if Site<>nil then begin
@@ -3252,7 +3424,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -3262,6 +3434,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -3323,6 +3496,7 @@
   HeaderFlatten                    := Settings.HeaderFlatten;
   HeaderFilled                     := Settings.HeaderFilled;
   HeaderHighlightFocused           := Settings.HeaderHighlightFocused;
+  DockSitesCanBeMinimized          := Settings.DockSitesCanBeMinimized;
 end;
 
 procedure TAnchorDockMaster.SaveSettings(Settings: TAnchorDockSettings);
@@ -3343,6 +3517,7 @@
   Settings.HeaderFlatten:=HeaderFlatten;
   Settings.HeaderFilled:=HeaderFilled;
   Settings.HeaderHighlightFocused:=HeaderHighlightFocused;
+  Settings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized;
 end;
 
 function TAnchorDockMaster.SettingsAreEqual(Settings: TAnchorDockSettings
@@ -3680,6 +3855,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -4119,6 +4295,8 @@
 end;
 
 procedure TAnchorDockHostSite.FreePages;
+var
+  i:Integer;
 begin
   FreeAndNil(FPages);
 end;
@@ -4233,6 +4411,14 @@
         akRight: NewBounds.Right:=AControl.Left+AControl.Width;
         akBottom: NewBounds.Bottom:=AControl.Top+AControl.Height;
         end;
+        if (sibling is TAnchorDockHostSite) then
+        if (sibling as TAnchorDockHostSite).FMinimized then begin
+          (sibling as TAnchorDockHostSite).FMinimized:=false;
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Parent:=(sibling as TAnchorDockHostSite);
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Visible:=True;
+          (sibling as TAnchorDockHostSite).FMinimizedControl:=nil;
+          (sibling as TAnchorDockHostSite).UpdateHeaderAlign;
+        end;
         Sibling.BoundsRect:=NewBounds;
       end;
     end;
@@ -4306,6 +4492,13 @@
       FSiteType:=adhstOneControl;
       OnlySiteLeft.Align:=alClient;
       Header.Parent:=Self;
+      if OnlySiteLeft.FMinimized then begin
+        OnlySiteLeft.FMinimized:=false;
+        OnlySiteLeft.FMinimizedControl.Parent:=OnlySiteLeft;
+        OnlySiteLeft.FMinimizedControl.Visible:=True;
+        OnlySiteLeft.FMinimizedControl:=nil;
+        UpdateHeaderAlign;
+      end;
       UpdateHeaderAlign;
 
       //debugln(['TAnchorDockHostSite.RemoveControlFromLayout.ConvertToOneControlType AFTER CONVERT "',Caption,'" to onecontrol OnlySiteLeft="',OnlySiteLeft.Caption,'"']);
@@ -4465,7 +4658,7 @@
     debugln(['TAnchorDockHostSite.Simplify ',DbgSName(Self),' ',DbgSName(AControl)]);
     if AControl is TAnchorDockHostSite then
       SimplifyOneControl
-    else if (AControl=nil) or (csDestroying in AControl.ComponentState) then
+    else if ((AControl=nil) or (csDestroying in AControl.ComponentState)) then
       DockMaster.NeedFree(Self);
   end;
 end;
@@ -4577,7 +4770,8 @@
     Result:=Controls[i];
     if Result.Owner<>Self then exit;
   end;
-  Result:=nil;
+  result:=FMinimizedControl;
+  //Result:=nil;
 end;
 
 function TAnchorDockHostSite.GetSiteCount: integer;
@@ -5165,6 +5359,102 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+begin
+  //Application.QueueAsyncCall(@AsyncMinimizeSite,0);
+  AsyncMinimizeSite(0);
+end;
+
+procedure TAnchorDockHostSite.AsyncMinimizeSite(Data: PtrInt);
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  fMinimization:=true;
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  if FMinimized then
+    AControl:=FMinimizedControl
+  else
+    AControl:=GetOneControl;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) or FMinimized then begin
+      FMinimized:=not FMinimized;
+      if FMinimized then begin
+        FMinimizedControl:=AControl;
+        AControl.Visible:=False;
+        AControl.Parent:=nil;
+      end else begin
+        AControl.Parent:=self;
+        AControl.Visible:=True;
+        FMinimizedControl:=nil;
+      end;
+      Splitter.Enabled:=AControl.Visible;
+      UpdateHeaderAlign;
+      Splitter.SetBoundsPercentually;
+    end;
+  end;
+  fMinimization:=false;
+end;
+
+procedure TAnchorDockHostSite.ShowMinimizedControl;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  SpliterRect,OverlappingFormRect:TRect;
+begin
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    SpliterRect:=Splitter.GetSpliterBoundsWithUnminimizedDockSites;
+    OverlappingFormRect:=BoundsRect;
+    case SplitterAnchorKind of
+         akTop:OverlappingFormRect.Top:=SpliterRect.Bottom;
+        akLeft:OverlappingFormRect.Left:=SpliterRect.Right;
+       akRight:OverlappingFormRect.Right:=SpliterRect.Left;
+      akBottom:OverlappingFormRect.Bottom:=SpliterRect.Top;
+    end;
+    DockMaster.FOverlappingForm:=TAnchorDockOverlappingForm.CreateNew(self);
+    DockMaster.FOverlappingForm.BoundsRect:=OverlappingFormRect;
+    DockMaster.FOverlappingForm.Parent:=GetParentFormOrDockPanel(self,false);
+    DockMaster.FOverlappingForm.AnchorDockHostSite:=self;
+    FMinimizedControl.Parent:=DockMaster.FOverlappingForm;
+    FMinimizedControl.Show;
+    DockMaster.ShowOverlappingForm;
+  end;
+end;
+
+procedure TAnchorDockHostSite.HideMinimizedControl;
+begin
+   FMinimizedControl.Hide;
+   FMinimizedControl.Parent:=nil;
+   FreeAndNil(DockMaster.FOverlappingForm);
+end;
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5306,9 +5596,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm))and(Pages=nil);
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5362,9 +5651,33 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+const
+OppositeAlign: array[TAnchorKind] of TAlign = (
+  alBottom, // akTop,
+  alRight,  // akLeft,
+  alLeft,   // akRight,
+  alTop     // akBottom
+  );
+OppositeAnchorKindAlign: array[TAnchorKind] of TADLHeaderPosition = (
+  adlhpBottom, // akTop,
+  adlhpRight,  // akLeft,
+  adlhpLeft,   // akRight,
+  adlhpTop     // akBottom
+  );
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      NeededHeaderPosition:=OppositeAnchorKindAlign[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5390,8 +5703,11 @@
 procedure TAnchorDockHostSite.UpdateHeaderShowing;
 begin
   if Header=nil then exit;
-  if HeaderNeedsShowing then
-    Header.Parent:=Self
+  if HeaderNeedsShowing then begin
+    Header.Parent:=Self;
+    Header.MinimizeButton.Visible:=DockMaster.DockSitesCanBeMinimized;
+    Header.MinimizeButton.Parent:=Header;
+  end
   else
     Header.Parent:=nil;
 end;
@@ -5432,7 +5748,7 @@
   if (SiteType=adhstOneControl) and (OneControl<>nil)
   and (not (OneControl is TAnchorDockHostSite)) then begin
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.Name:=OneControl.Name;
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if (SiteType in [adhstLayout,adhstOneControl]) then begin
@@ -5450,7 +5766,7 @@
         Splitter.SaveLayout(ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if SiteType=adhstPages then begin
     LayoutNode.NodeType:=adltnPages;
@@ -5461,7 +5777,7 @@
         Site.SaveLayout(LayoutTree,ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else
     LayoutNode.NodeType:=adltnNone;
@@ -5476,6 +5792,9 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
+  fMinimization:=false;
+  FMinimizedControl:=Nil;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5490,13 +5809,13 @@
 end;
 
 destructor TAnchorDockHostSite.Destroy;
-//var i: Integer;
+var i: Integer;
 begin
-  //debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
-  {for i:=0 to ComponentCount-1 do
+  debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
+  for i:=0 to ComponentCount-1 do
     debugln(['TAnchorDockHostSite.Destroy Component ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   for i:=0 to ControlCount-1 do
-    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);}
+    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);
   FreePages;
   inherited Destroy;
 end;
@@ -5569,6 +5888,13 @@
   end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+begin
+  if Parent is TAnchorDockHostSite then begin
+    TAnchorDockHostSite(Parent).MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5640,6 +5966,13 @@
       r.Right:=CloseButton.Left-1;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+1
+    else
+      r.Right:=MinimizeButton.Left-1;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,7 +6061,14 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
@@ -5739,14 +6079,63 @@
     DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
 end;
 
+procedure  TAnchorDockHeader.MouseMove(Shift: TShiftState; X,Y: Integer);
+begin
+  inherited MouseMove(Shift, X, Y);
+  if parent<>nil then
+    if parent is TAnchorDockHostSite then
+      if (parent as TAnchorDockHostSite).FMinimized then
+        if DockMaster.FOverlappingForm=nil then
+          if FMouseTimeStartX=EmptyMouseTimeStartX then
+            StartMouseNoMoveTimer(X, Y)
+          else begin
+            if (abs(FMouseTimeStartX-X)>MouseNoMoveDelta)or(abs(FMouseTimeStartY-Y)>MouseNoMoveDelta)then
+            StopMouseNoMoveTimer;
+          end;
+end;
+
+procedure TAnchorDockHeader.MouseLeave;
+begin
+  inherited;
+  StopMouseNoMoveTimer;
+end;
+
+procedure TAnchorDockHeader.StartMouseNoMoveTimer(X, Y: Integer);
+begin
+  if MouseNoMoveTimer.Enabled then MouseNoMoveTimer.Enabled:=false;
+  MouseNoMoveTimer.Interval:=MouseNoMoveTime;
+  MouseNoMoveTimer.OnTimer:=@DoMouseNoMoveTimer;
+  MouseNoMoveTimer.Enabled:=true;
+end;
+
+procedure TAnchorDockHeader.StopMouseNoMoveTimer;
+begin
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  MouseNoMoveTimer.OnTimer:=nil;
+  MouseNoMoveTimer.Enabled:=false;
+end;
+
+procedure TAnchorDockHeader.DoMouseNoMoveTimer(Sender: TObject);
+begin
+  StopMouseNoMoveTimer;
+  if parent<>nil then
+    if parent is TAnchorDockHostSite then
+      if (parent as TAnchorDockHostSite).FMinimized then
+        (parent as TAnchorDockHostSite).ShowMinimizedControl;
+end;
+
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alTop;
       CloseButton.Align:=alTop;
+    end;
   end else begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alRight;
       CloseButton.Align:=alRight;
+    end;
   end;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
@@ -5787,9 +6176,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,11 +6188,22 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
   PopupMenu:=DockMaster.GetPopupMenu;
   fFocused:=false;
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
 end;
 
 { TAnchorDockCloseButton }
@@ -5844,6 +6244,44 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMinButtonNormal;
+    if not IsEnabled then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonDisabled{$ELSE}twMinButtonDisabled{$ENDIF}
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonPushed{$ELSE}twMinButtonPushed{$ENDIF}
+    else
+    if FState = bsHot then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonHot{$ELSE}twMinButtonHot{$ENDIF}
+    else
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF};
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails({$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF})) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6505,32 +6943,58 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
@@ -6560,14 +7024,47 @@
   end;
 end;
 
+function TAnchorDockSplitter.GetSpliterBoundsWithUnminimizedDockSites:TRect;
+var
+  NewLeft, NewTop: Integer;
+begin
+  if ResizeAnchor in [akLeft,akRight] then
+  begin
+    if DockParentClientSize.cx> 0 then
+    begin
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+      else
+        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+      NewTop := Top;
+    end;
+  end else
+  begin
+    if DockParentClientSize.cy> 0 then
+    begin
+      NewLeft := Left;
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewTop := Round(FPercentPosition*Parent.ClientHeight)
+      else
+        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    end;
+  end;
+  result:=Rect(NewLeft,NewTop,NewLeft+Width,NewTop+Height);
+end;
+
 procedure TAnchorDockSplitter.SaveLayout(
   LayoutNode: TAnchorDockLayoutTreeNode);
+var
+  NewLeft, NewTop: Integer;
 begin
   if ResizeAnchor in [akLeft,akRight] then
     LayoutNode.NodeType:=adltnSplitterVertical
   else
     LayoutNode.NodeType:=adltnSplitterHorizontal;
-  LayoutNode.Assign(Self);
+  LayoutNode.Assign(Self,false,false);
+  if not Enabled then begin
+    LayoutNode.BoundsRect:=GetSpliterBoundsWithUnminimizedDockSites;
+  end
 end;
 
 function TAnchorDockSplitter.HasOnlyOneSibling(Side: TAnchorKind; MinPos,
@@ -6782,6 +7279,20 @@
   PopupMenu:=DockMaster.GetPopupMenu;
 end;
 
+{ TAnchorDockOverlappingForm }
+
+constructor TAnchorDockOverlappingForm.CreateNew(AOwner: TComponent; Num: Integer = 0);
+begin
+  inherited;
+  BorderStyle:=bsNone;
+  AnchorDockHostSite:=nil;
+end;
+
+procedure TAnchorDockOverlappingForm.MouseLeave;
+begin
+  inherited;
+end;
+
 { TAnchorDockPage }
 
 procedure TAnchorDockPage.UpdateDockCaption(Exclude: TControl);
@@ -6835,9 +7346,11 @@
 
 initialization
   DockMaster:=TAnchorDockMaster.Create(nil);
+  MouseNoMoveTimer:=TTimer.Create(nil);
 
 finalization
   FreeAndNil(DockMaster);
+  FreeAndNil(MouseNoMoveTimer);
 
 end.
 
Index: components/anchordocking/anchordockoptionsdlg.lfm
===================================================================
--- components/anchordocking/anchordockoptionsdlg.lfm	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.lfm	(working copy)
@@ -1,11 +1,13 @@
 object AnchorDockOptionsFrame: TAnchorDockOptionsFrame
   Left = 0
-  Height = 482
+  Height = 567
   Top = 0
-  Width = 416
-  ClientHeight = 482
-  ClientWidth = 416
+  Width = 490
+  ClientHeight = 567
+  ClientWidth = 490
+  DesignTimePPI = 113
   OnClick = FrameClick
+  ParentFont = False
   TabOrder = 0
   DesignLeft = 513
   DesignTop = 189
@@ -12,14 +14,15 @@
   object DragThresholdLabel: TLabel
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
-    Left = 10
-    Height = 13
-    Top = 10
-    Width = 111
-    BorderSpacing.Left = 10
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 12
+    Width = 122
+    BorderSpacing.Left = 12
+    BorderSpacing.Top = 12
     Caption = 'DragThresholdLabel'
     ParentColor = False
+    ParentFont = False
   end
   object DragThresholdTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdLabel
@@ -27,15 +30,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 23
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 31
+    Width = 466
     Max = 20
     OnChange = DragThresholdTrackBarChange
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Right = 10
+    BorderSpacing.Right = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 1
@@ -46,12 +50,13 @@
     AnchorSideTop.Control = DragThresholdLabel
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
-    Left = 127
-    Height = 23
-    Top = 5
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 141
+    Height = 27
+    Top = 8
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 20
+    ParentFont = False
     TabOrder = 0
     Visible = False
   end
@@ -59,13 +64,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = DragThresholdTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 79
-    Width = 103
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 97
+    Width = 112
+    BorderSpacing.Top = 12
     Caption = 'SplitterWidthLabel'
     ParentColor = False
+    ParentFont = False
   end
   object SplitterWidthTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdTrackBar
@@ -73,14 +79,15 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 92
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 116
+    Width = 466
     Min = 1
     OnChange = SplitterWidthTrackBarChange
     Position = 1
     Anchors = [akTop, akLeft, akRight]
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 3
@@ -89,12 +96,13 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = SplitterWidthTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 142
-    Width = 160
-    BorderSpacing.Top = 4
+    Left = 12
+    Height = 23
+    Top = 175
+    Width = 169
+    BorderSpacing.Top = 5
     Caption = 'ScaleOnResizeCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 4
@@ -103,12 +111,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 166
-    Width = 149
+    Left = 12
+    Height = 23
+    Top = 198
+    Width = 160
     Caption = 'ShowHeaderCheckBox'
     OnChange = ShowHeaderCheckBoxChange
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 5
@@ -117,12 +126,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ShowHeaderCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 190
-    Width = 191
-    BorderSpacing.Left = 15
+    Left = 30
+    Height = 23
+    Top = 221
+    Width = 208
+    BorderSpacing.Left = 18
     Caption = 'ShowHeaderCaptionCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 6
@@ -131,11 +141,12 @@
     AnchorSideLeft.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 214
-    Width = 249
+    Left = 30
+    Height = 23
+    Top = 244
+    Width = 272
     Caption = 'HideHeaderCaptionForFloatingCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 7
@@ -147,15 +158,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 122
+    Left = 136
     Height = 27
-    Top = 286
-    Width = 284
+    Top = 313
+    Width = 342
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 6
-    BorderSpacing.Right = 10
-    ItemHeight = 0
+    BorderSpacing.Left = 7
+    BorderSpacing.Right = 12
+    ItemHeight = 19
     OnDrawItem = HeaderStyleComboBoxDrawItem
+    ParentFont = False
     Style = csDropDownList
     TabOrder = 10
   end
@@ -163,23 +175,25 @@
     AnchorSideLeft.Control = ShowHeaderCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrCenter
-    Left = 20
-    Height = 13
-    Top = 293
-    Width = 96
-    BorderSpacing.Left = 10
+    Left = 24
+    Height = 19
+    Top = 317
+    Width = 105
+    BorderSpacing.Left = 12
     Caption = 'HeaderStyleLabel'
     ParentColor = False
+    ParentFont = False
   end
   object FlattenHeadersCheckBox: TCheckBox
     AnchorSideLeft.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 238
-    Width = 164
+    Left = 30
+    Height = 23
+    Top = 267
+    Width = 175
     Caption = 'FlattenHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 8
@@ -188,11 +202,12 @@
     AnchorSideLeft.Control = FlattenHeadersCheckBox
     AnchorSideTop.Control = FlattenHeadersCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 262
-    Width = 154
+    Left = 30
+    Height = 23
+    Top = 290
+    Width = 164
     Caption = 'FilledHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 9
@@ -201,11 +216,12 @@
     AnchorSideLeft.Control = FilledHeadersCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 313
-    Width = 175
+    Left = 30
+    Height = 23
+    Top = 340
+    Width = 189
     Caption = 'HighlightFocusedCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 11
@@ -215,13 +231,14 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = SplitterWidthLabel
     AnchorSideTop.Side = asrCenter
-    Left = 119
-    Height = 23
-    Top = 74
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 131
+    Height = 27
+    Top = 93
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 10
     MinValue = 1
+    ParentFont = False
     TabOrder = 2
     Value = 1
     Visible = False
@@ -228,15 +245,16 @@
   end
   object HeaderAlignTopLabel: TLabel
     AnchorSideLeft.Control = DragThresholdLabel
-    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Control = DockSitesCanBeMinimized
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 347
-    Width = 117
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 398
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignTopLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignTopTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -244,10 +262,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 360
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 417
+    Width = 466
     Frequency = 10
     Max = 150
     OnChange = HeaderAlignTopTrackBarChange
@@ -254,7 +272,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 13
@@ -264,12 +283,13 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignTopLabel
     AnchorSideTop.Side = asrCenter
-    Left = 133
-    Height = 23
-    Top = 342
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 394
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 150
+    ParentFont = False
     TabOrder = 12
     Visible = False
   end
@@ -277,13 +297,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = HeaderAlignTopTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 417
-    Width = 120
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 484
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignLeftLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignLeftTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -291,10 +312,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 430
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 503
+    Width = 466
     Frequency = 10
     Max = 200
     OnChange = HeaderAlignLeftTrackBarChange
@@ -301,7 +322,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 15
@@ -311,13 +333,28 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignLeftLabel
     AnchorSideTop.Side = asrCenter
-    Left = 136
-    Height = 23
-    Top = 412
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 480
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 200
+    ParentFont = False
     TabOrder = 14
     Visible = False
   end
+  object DockSitesCanBeMinimized: TCheckBox
+    AnchorSideLeft.Control = FilledHeadersCheckBox
+    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Side = asrBottom
+    Left = 30
+    Height = 23
+    Top = 363
+    Width = 185
+    Caption = 'DockSitesCanBeMinimized'
+    ParentFont = False
+    ParentShowHint = False
+    ShowHint = True
+    TabOrder = 16
+  end
 end
Index: components/anchordocking/anchordockoptionsdlg.pas
===================================================================
--- components/anchordocking/anchordockoptionsdlg.pas	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.pas	(working copy)
@@ -37,6 +37,7 @@
     HeaderStyleLabel: TLabel;
     HideHeaderCaptionForFloatingCheckBox: TCheckBox;
     HighlightFocusedCheckBox: TCheckBox;
+    DockSitesCanBeMinimized: TCheckBox;
     ScaleOnResizeCheckBox: TCheckBox;
     ShowHeaderCaptionCheckBox: TCheckBox;
     ShowHeaderCheckBox: TCheckBox;
@@ -299,6 +300,7 @@
   HeaderStyleLabel.Enabled:=HasHeaders;
   HeaderStyleComboBox.Enabled:=HasHeaders;
   HighlightFocusedCheckBox.Enabled:=HasHeaders;
+  DockSitesCanBeMinimized.Enabled:=HasHeaders;
 end;
 
 constructor TAnchorDockOptionsFrame.Create(TheOwner: TComponent);
@@ -356,6 +358,7 @@
   TheSettings.HeaderFilled:=FilledHeadersCheckBox.Checked;
   TheSettings.HeaderStyle:=TADHeaderStyle(HeaderStyleComboBox.ItemIndex);
   TheSettings.HeaderHighlightFocused:=HighlightFocusedCheckBox.Checked;
+  TheSettings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized.Checked;
 end;
 
 procedure TAnchorDockOptionsFrame.LoadFromSettings(
@@ -429,6 +432,10 @@
   HighlightFocusedCheckBox.Checked:=TheSettings.HeaderHighlightFocused;
   HighlightFocusedCheckBox.Caption:=adrsHighlightFocused;
   HighlightFocusedCheckBox.Hint:=adrsHighlightFocusedHint;
+
+  DockSitesCanBeMinimized.Checked:=TheSettings.DockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Caption:=adrsDockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Hint:=adrsDockSitesCanBeMinimizedHint;
 end;
 
 end.
Index: components/anchordocking/anchordockpanel.pas
===================================================================
--- components/anchordocking/anchordockpanel.pas	(revision 59428)
+++ components/anchordocking/anchordockpanel.pas	(working copy)
@@ -55,7 +55,7 @@
   begin
 
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,false);
     LayoutNode.Name:={OneControl.}Name;
 
     TAnchorDockHostSite(OneControl).SaveLayout(LayoutTree,LayoutNode);
Index: components/anchordocking/anchordockstorage.pas
===================================================================
--- components/anchordocking/anchordockstorage.pas	(revision 59428)
+++ components/anchordocking/anchordockstorage.pas	(working copy)
@@ -64,6 +64,7 @@
     FTabPosition: TTabPosition;
     FWindowState: TWindowState;
     FControlLocation: TADLControlLocation;
+    FMinimized: Boolean;
     function GetAnchors(Site: TAnchorKind): string;
     function GetBottom: integer;
     function GetHeight: integer;
@@ -90,6 +91,7 @@
     procedure SetTop(const AValue: integer);
     procedure SetWidth(const AValue: integer);
     procedure SetWindowState(const AValue: TWindowState);
+    procedure SetMinimized(const AValue: boolean);
   public
     constructor Create;
     destructor Destroy; override;
@@ -96,7 +98,7 @@
     procedure Clear;
     function IsEqual(Node: TAnchorDockLayoutTreeNode): boolean;
     procedure Assign(Node: TAnchorDockLayoutTreeNode); overload;
-    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean=false); overload;
+    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean); overload;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
     procedure LoadFromConfig(Path: string; Config: TRttiXMLConfig); overload;
     procedure SaveToConfig(Config: TConfigStorage); overload;
@@ -106,7 +108,7 @@
     procedure CheckConsistency; virtual;
 
     // simplifying
-    procedure Simplify(ExistingNames: TStrings);
+    procedure Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
     procedure DeleteNode(ChildNode: TAnchorDockLayoutTreeNode);
     function FindNodeBoundSplitter(ChildNode: TAnchorDockLayoutTreeNode;
                                    Side: TAnchorKind): TAnchorDockLayoutTreeNode;
@@ -135,6 +137,7 @@
     property Monitor: integer read FMonitor write SetMonitor;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property TabPosition: TTabPosition read FTabPosition write SetTabPosition;
+    property Minimized: Boolean read FMinimized write SetMinimized;
     function Count: integer;
     function IsSplitter: boolean;
     function IsRootWindow: boolean;
@@ -988,6 +991,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockLayoutTreeNode.SetMinimized(const AValue: boolean);
+begin
+  if FMinimized=AValue then exit;
+  FMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockLayoutTreeNode.SetTop(const AValue: integer);
 begin
   if Top=AValue then exit;
@@ -1084,6 +1094,7 @@
   BoundSplitterPos:=Node.BoundSplitterPos;
   WorkAreaRect:=Node.WorkAreaRect;
   Monitor:=Node.Monitor;
+  Minimized:=Node.Minimized;
   for a:=low(TAnchorKind) to high(TAnchorKind) do
     Anchors[a]:=Node.Anchors[a];
   while Count>Node.Count do Nodes[Count-1].Free;
@@ -1098,9 +1109,10 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean=false);
+procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean);
 var
   AnchorControl: TControl;
+  ParentForm:TCustomForm;
   a: TAnchorKind;
 begin
   Name:=AControl.Name;
@@ -1109,12 +1121,18 @@
   else
     BoundsRect:=AControl.BoundsRect;
   Align:=AControl.Align;
+  Minimized:=AMinimized;
   if (AControl.Parent=nil) and (AControl is TCustomForm) then begin
     WindowState:=TCustomForm(AControl).WindowState;
     Monitor:=TCustomForm(AControl).Monitor.MonitorNum;
     WorkAreaRect:=TCustomForm(AControl).Monitor.WorkareaRect;
-  end else
-    WindowState:=GetParentForm(AControl).WindowState;
+  end else begin
+    ParentForm:=GetParentForm(AControl);
+    if assigned(ParentForm) then
+      WindowState:=ParentForm.WindowState
+    else
+      WindowState:=wsNormal;
+  end;
   if AControl is TCustomTabControl then
     TabPosition:=TCustomTabControl(AControl).TabPosition
   else
@@ -1137,6 +1155,7 @@
   Clear;
   Name:=Config.GetValue('Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue('Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue('Minimized',false);
   Left:=Config.GetValue('Bounds/Left',0);
   Top:=Config.GetValue('Bounds/Top',0);
   Width:=Config.GetValue('Bounds/Width',0);
@@ -1171,6 +1190,7 @@
   Clear;
   Name:=Config.GetValue(Path+'Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue(Path+'Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue(Path+'Minimized',false);
   Left:=Config.GetValue(Path+'Bounds/Left',0);
   Top:=Config.GetValue(Path+'Bounds/Top',0);
   Width:=Config.GetValue(Path+'Bounds/Width',0);
@@ -1219,6 +1239,7 @@
                                           ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue('Header/TabPosition',ADLTabPostionNames[TabPosition],
                                              ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue('Minimized',Minimized,False);
   Config.SetDeleteValue('Monitor',Monitor,0);
   Config.SetDeleteValue('ChildCount',Count,0);
   for i:=1 to Count do begin
@@ -1252,6 +1273,7 @@
                                                ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue(Path+'Header/TabPosition',ADLTabPostionNames[TabPosition],
                                                   ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue(Path+'Minimized',Minimized,False);
   Config.SetDeleteValue(Path+'Monitor',Monitor,0);
   Config.SetDeleteValue(Path+'ChildCount',Count,0);
   for i:=1 to Count do
@@ -1397,7 +1419,7 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings);
+procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
 { Simplification rules:
    1. Control nodes without existing name are deleted.
    2. Empty layouts and pages are deleted
@@ -1406,16 +1428,18 @@
 var
   i: Integer;
   ChildNode: TAnchorDockLayoutTreeNode;
+  NodeMinimized:boolean;
 begin
   // simplify children
   i:=Count-1;
   while i>=0 do begin
     ChildNode:=Nodes[i];
-    ChildNode.Simplify(ExistingNames);
+    NodeMinimized:=ParentMinimized or ChildNode.Minimized;
+    ChildNode.Simplify(ExistingNames,NodeMinimized);
 
     if (ChildNode.NodeType=adltnControl) then begin
       // leaf node => check if there is a control
-      if (ChildNode.Name='') or (ExistingNames.IndexOf(ChildNode.Name)<0) then
+      if (ChildNode.Name='') or ((ExistingNames.IndexOf(ChildNode.Name)<0) and (not NodeMinimized)) then
         DeleteNode(ChildNode);
     end else if ChildNode.IsSplitter then begin
       // splitter
@@ -1424,7 +1448,7 @@
         ChildNode[0].Free;
     end else if ChildNode.NodeType=adltnCustomSite then begin
       // custom dock site
-    end else if ChildNode.Count=0 then begin
+    end else if (ChildNode.Count=0)and(not NodeMinimized) then begin
       // inner node without child => delete
       DeleteNode(ChildNode);
     end else if (ChildNode.Count=1)
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59428)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';
@@ -82,6 +83,8 @@
   adrsFilledHeadersHint = 'Fill headers of docked controls';
   adrsHighlightFocused = 'Highlight focused';
   adrsHighlightFocusedHint = 'Highlight header of focused docked control';
+  adrsDockSitesCanBeMinimized = 'Dock sites can be minimized';
+  adrsDockSitesCanBeMinimizedHint = 'Dock sites can be minimized';
 
 implementation
 
Index: components/anchordocking/design/anchordesktopoptions.pas
===================================================================
--- components/anchordocking/design/anchordesktopoptions.pas	(revision 59428)
+++ components/anchordocking/design/anchordesktopoptions.pas	(working copy)
@@ -272,7 +272,7 @@
         // custom dock site
         LayoutNode:=FTree.NewNode(FTree.Root);
         LayoutNode.NodeType:=adltnCustomSite;
-        LayoutNode.Assign(AForm);
+        LayoutNode.Assign(AForm,false,false);
         // can have one normal dock site
         Site:=TAnchorDockManager(AForm.DockManager).GetChildSite;
         if Site<>nil then begin
@@ -287,7 +287,7 @@
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    FTree.Root.Simplify(VisibleControls);
+    FTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59428)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -109,6 +109,11 @@
 const ADAutoSizingReason = 'TAnchorDockMaster Delayed';
 {$ENDIF}
 
+const EmptyMouseTimeStartX=low(Integer);
+      MouseNoMoveDelta=5;
+      MouseNoMoveTime=500;
+      HideOverlappingFormByMouseLoseTime=500;
+
 type
   TAnchorDockHostSite = class;
 
@@ -123,6 +128,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +146,12 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
+    FMouseTimeStartX,FMouseTimeStartY:Integer;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -147,6 +163,11 @@
           PreferredHeight: integer; WithThemeSpace: Boolean); override;
     procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X,
              Y: Integer); override;
+    procedure MouseMove(Shift: TShiftState; X,Y: Integer); override;
+    procedure MouseLeave;  override;
+    procedure StartMouseNoMoveTimer(X, Y: Integer);
+    procedure StopMouseNoMoveTimer;
+    procedure DoMouseNoMoveTimer(Sender: TObject);
     procedure UpdateHeaderControls;
     procedure SetAlign(Value: TAlign); override;
     procedure DoOnShowHint(HintInfo: PHintInfo); override;
@@ -154,6 +175,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -190,6 +212,7 @@
     procedure SetBoundsKeepDockBounds(ALeft, ATop, AWidth, AHeight: integer); // movement for scaling keeps the DockBounds
     function SideAnchoredControlCount(Side: TAnchorKind): integer;
     function HasAnchoredControls: boolean;
+    function GetSpliterBoundsWithUnminimizedDockSites:TRect;
     procedure SaveLayout(LayoutNode: TAnchorDockLayoutTreeNode);
     function HasOnlyOneSibling(Side: TAnchorKind; MinPos, MaxPos: integer): TControl;
     property DockRestoreBounds: TRect read FDockRestoreBounds write FDockRestoreBounds;
@@ -241,6 +264,15 @@
   end;
   TAnchorDockPageControlClass = class of TAnchorDockPageControl;
 
+
+  TAnchorDockOverlappingForm = class(TCustomForm)
+  protected
+    procedure MouseLeave;  override;
+  public
+    AnchorDockHostSite:TAnchorDockHostSite;
+    constructor CreateNew(AOwner: TComponent; Num: Integer = 0); override;
+  end;
+
   { TAnchorDockHostSite
     This form is the dockhostsite for all controls.
     When docked together they build a tree structure with the docked controls
@@ -262,7 +294,10 @@
     FPages: TAnchorDockPageControl;
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
-    fUpdateLayout: integer;
+    fUpdateLayout: Integer;
+    FMinimized: Boolean;
+    fMinimization: Boolean;
+    FMinimizedControl: TControl;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +354,10 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
+    procedure AsyncMinimizeSite(Data: PtrInt);
+    procedure ShowMinimizedControl;
+    procedure HideMinimizedControl;
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -431,6 +470,7 @@
     FShowHeader: boolean;
     FShowHeaderCaption: boolean;
     FSplitterWidth: integer;
+    FDockSitecCanBeMinimized: boolean;
     procedure SetAllowDragging(AValue: boolean);
     procedure SetDockOutsideMargin(AValue: integer);
     procedure SetDockParentMargin(AValue: integer);
@@ -448,6 +488,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitecCanBeMinimized(AValue: boolean);
   public
     property DragTreshold: integer read FDragTreshold write SetDragTreshold;
     property DockOutsideMargin: integer read FDockOutsideMargin write SetDockOutsideMargin;
@@ -466,6 +507,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused;
+    property DockSitesCanBeMinimized: boolean read FDockSitecCanBeMinimized write SetDockSitecCanBeMinimized;
     procedure IncreaseChangeStamp; inline;
     property ChangeStamp: integer read FChangeStamp;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
@@ -502,6 +544,7 @@
     FHeaderFlatten: boolean;
     FHeaderFilled: boolean;
     FHeaderHighlightFocused: boolean;
+    FDockSitesCanBeMinimized: boolean;
     FIdleConnected: Boolean;
     FManagerClass: TAnchorDockManagerClass;
     FOnCreateControl: TADCreateControlEvent;
@@ -531,6 +574,7 @@
     fPopupMenu: TPopupMenu;
     // Used by RestoreLayout:
     WorkArea, SrcWorkArea: TRect;
+    FOverlappingForm:TAnchorDockOverlappingForm;
 
     function GetControls(Index: integer): TControl;
     function GetLocalizedHeaderHint: string;
@@ -541,6 +585,8 @@
     function GetNodeSite(Node: TAnchorDockLayoutTreeNode): TAnchorDockHostSite;
     procedure MapTreeToControls(Tree: TAnchorDockLayoutTree);
     function RestoreLayout(Tree: TAnchorDockLayoutTree; Scale: boolean): boolean;
+    procedure SetMinimizedState(Tree: TAnchorDockLayoutTree);
+    procedure SetnodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
     procedure EnableAllAutoSizing;
     procedure ClearLayoutProperties(AControl: TControl; NewAlign: TAlign = alClient);
     procedure PopupMenuPopup(Sender: TObject);
@@ -561,6 +607,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitesCanBeMinimized(AValue: boolean);
 
     procedure SetShowMenuItemShowHeader(AValue: boolean);
     procedure SetupSite(Site: TWinControl; ANode: TAnchorDockLayoutTreeNode;
@@ -584,8 +631,12 @@
     procedure SetHideHeaderCaptionFloatingControl(const AValue: boolean);
     procedure SetSplitterWidth(const AValue: integer);
     procedure OnIdle(Sender: TObject; var Done: Boolean);
+    procedure StartHideOverlappingTimer;
+    procedure StopHideOverlappingTimer;
     procedure AsyncSimplify({%H-}Data: PtrInt);
   public
+    procedure ShowOverlappingForm;
+    procedure HideOverlappingForm(Sender: TObject);
     constructor Create(AOwner: TComponent); override;
     destructor Destroy; override;
     function FullRestoreLayout(Tree: TAnchorDockLayoutTree; Scale: Boolean): Boolean;
@@ -680,6 +731,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten default true;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled default true;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused default false;
+    property DockSitesCanBeMinimized: boolean read FDockSitesCanBeMinimized write SetDockSitesCanBeMinimized default false;
 
     property SplitterWidth: integer read FSplitterWidth write SetSplitterWidth default 4;
     property ScaleOnResize: boolean read FScaleOnResize write SetScaleOnResize default true; // scale children when resizing a site
@@ -698,6 +750,7 @@
 
 var
   DockMaster: TAnchorDockMaster = nil;
+  DockTimer: TTimer = nil;
 
 const
   ADHeaderStyleNames: array[TADHeaderStyle] of string = (
@@ -970,6 +1023,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -1361,6 +1435,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockSettings.SetDockSitecCanBeMinimized(AValue: boolean);
+begin
+  if FDockSitecCanBeMinimized=AValue then Exit;
+  FDockSitecCanBeMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockSettings.Assign(Source: TAnchorDockSettings);
 begin
   FAllowDragging := Source.FAllowDragging;
@@ -1381,6 +1462,7 @@
   FShowHeaderCaption := Source.FShowHeaderCaption;
   FSplitterWidth := Source.FSplitterWidth;
   FHeaderHighlightFocused:=Source.FHeaderHighlightFocused;
+  FDockSitecCanBeMinimized:=Source.FDockSitecCanBeMinimized;
 end;
 
 procedure TAnchorDockSettings.IncreaseChangeStamp;
@@ -1407,6 +1489,7 @@
   HeaderFlatten:=Config.GetValue('HeaderFlatten',true);
   HeaderFilled:=Config.GetValue('HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue('HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue('DockSitecCanBeMinimized',False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1429,6 +1512,7 @@
   Config.SetDeleteValue(Path+'HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue(Path+'HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue(Path+'HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue(Path+'DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
 end;
 
 procedure TAnchorDockSettings.SaveToConfig(Config: TConfigStorage);
@@ -1450,6 +1534,7 @@
   Config.SetDeleteValue('HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue('HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue('HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue('DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1472,6 +1557,7 @@
       and (HeaderFlatten=Settings.HeaderFlatten)
       and (HeaderFilled=Settings.HeaderFilled)
       and (HeaderHighlightFocused=Settings.HeaderHighlightFocused)
+      and (DockSitesCanBeMinimized=Settings.DockSitesCanBeMinimized)
       ;
 end;
 
@@ -1494,6 +1580,7 @@
   HeaderFlatten:=Config.GetValue(Path+'HeaderFlatten',true);
   HeaderFilled:=Config.GetValue(Path+'HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue(Path+'HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue(Path+'DockSitecCanBeMinimized',False);
 end;
 
 { TAnchorDockMaster }
@@ -2021,6 +2108,8 @@
     aHostSite:=TAnchorDockHostSite(Site);
     aHostSite.Header.HeaderPosition:=ANode.HeaderPosition;
     aHostSite.DockRestoreBounds:=NewBounds;
+    //aHostSite.FMinimized:=ANode.Minimized;
+    //we update aHostSite.FMinimized in TAnchorDockMaster.SetMinimizedState
     if (ANode.NodeType<>adltnPages) and (aHostSite.Pages<>nil) then
       aHostSite.FreePages;
   end;
@@ -2040,6 +2129,25 @@
   fTreeNameToDocker[Node.Name]:=Result;
 end;
 
+procedure TAnchorDockMaster.SetNodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
+var
+  HostSite:TAnchorDockHostSite;
+  i:integer;
+begin
+  HostSite:=GetNodeSite(ANode);
+  if Assigned(HostSite) then
+    if HostSite.FMinimized<>ANode.Minimized then
+      Application.QueueAsyncCall(@HostSite.AsyncMinimizeSite,0);
+      //HostSite.MinimizeSite;
+  for i:=0 to ANode.Count-1 do
+    SetnodeMinimizedState(ANode.Nodes[i]);
+end;
+
+procedure TAnchorDockMaster.SetMinimizedState(Tree: TAnchorDockLayoutTree);
+begin
+  SetnodeMinimizedState(Tree.Root);
+end;
+
 function TAnchorDockMaster.RestoreLayout(Tree: TAnchorDockLayoutTree;
   Scale: boolean): boolean;
 
@@ -2193,7 +2301,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -2358,7 +2466,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -2368,6 +2476,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -2422,11 +2531,40 @@
   OptionsChanged;
 end;
 
+procedure TAnchorDockMaster.StartHideOverlappingTimer;
+begin
+  if not DockTimer.Enabled then begin
+    DockTimer.Interval:=HideOverlappingFormByMouseLoseTime;
+    DockTimer.OnTimer:=@HideOverlappingForm;
+    DockTimer.Enabled:=true;
+  end;
+end;
+
+procedure TAnchorDockMaster.StopHideOverlappingTimer;
+begin
+  DockTimer.Enabled:=False;
+  DockTimer.Interval:=0;
+  DockTimer.OnTimer:=nil;
+end;
+
 procedure TAnchorDockMaster.OnIdle(Sender: TObject; var Done: Boolean);
+var
+  MousePos: TPoint;
+  Bounds:Trect;
 begin
   if Done then ;
-  IdleConnected:=false;
   Restoring:=false;
+  if FOverlappingForm=nil then
+    IdleConnected:=false
+  else begin
+    GetCursorPos(MousePos);
+    Bounds.TopLeft:=FOverlappingForm.ClientToScreen(point(0,0));
+    Bounds.BottomRight:=FOverlappingForm.ClientToScreen(point(FOverlappingForm.Width,FOverlappingForm.Height));
+    if not PtInRect(Bounds,MousePos) then
+      StartHideOverlappingTimer
+    else
+      StopHideOverlappingTimer;
+  end;
 end;
 
 procedure TAnchorDockMaster.AsyncSimplify(Data: PtrInt);
@@ -2514,6 +2652,24 @@
   InvalidateHeaders;
 end;
 
+procedure TAnchorDockMaster.SetDockSitesCanBeMinimized(AValue: boolean);
+var
+  i:integer;
+  Site: TAnchorDockHostSite;
+begin
+  if FDockSitesCanBeMinimized=AValue then Exit;
+  FDockSitesCanBeMinimized:=AValue;
+  for i:=0 to ComponentCount-1 do begin
+    Site:=TAnchorDockHostSite(Components[i]);
+    if not (Site is TAnchorDockHostSite) then continue;
+    if (Site.Header<>nil) then begin
+      DisableControlAutoSizing(Site);
+      Site.UpdateHeaderShowing;
+    end;
+  end;
+  EnableAllAutoSizing;
+  OptionsChanged;
+end;
 procedure TAnchorDockMaster.SetScaleOnResize(AValue: boolean);
 begin
   if FScaleOnResize=AValue then Exit;
@@ -2668,6 +2824,20 @@
     EnableAllAutoSizing;
 end;
 
+procedure TAnchorDockMaster.ShowOverlappingForm;
+begin
+  FOverlappingForm.Show;
+  IdleConnected:=true;
+end;
+
+procedure TAnchorDockMaster.HideOverlappingForm(Sender: TObject);
+begin
+  StopHideOverlappingTimer;
+  FOverlappingForm.Hide;
+  FOverlappingForm.AnchorDockHostSite.HideMinimizedControl;
+  IdleConnected:=false;
+end;
+
 constructor TAnchorDockMaster.Create(AOwner: TComponent);
 begin
   inherited Create(AOwner);
@@ -2698,14 +2868,14 @@
   FPageClass:=TAnchorDockPage;
   FRestoreLayouts:=TAnchorDockRestoreLayouts.Create;
   FHeaderHighlightFocused:=false;
+  FDockSitesCanBeMinimized:=false;
+  FOverlappingForm:=nil;
 end;
 
 destructor TAnchorDockMaster.Destroy;
 var
   AControl: TControl;
-  {$IFDEF VerboseAnchorDocking}
-  i: Integer;
-  {$ENDIF}
+  i, j: Integer;
 begin
   QueueSimplify:=false;
   FreeAndNil(FRestoreLayouts);
@@ -2727,6 +2897,12 @@
     debugln(['TAnchorDockMaster.Destroy ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   end;
   {$ENDIF}
+  for i:=0 to ComponentCount-1 do begin
+    for j:=0 to ComponentCount-1 do begin
+      if i<>j then
+        TControl(Components[i]).RemoveAllHandlersOfObject(TControl(Components[j]));
+  end;
+  end;
   inherited Destroy;
 end;
 
@@ -3018,7 +3194,8 @@
   i:=Screen.CustomFormCount-1;
   while i>=0 do begin
     AForm:=GetParentForm(Screen.CustomForms[i]);
-    AForm.Hide;
+    if Assigned(AForm)then
+      AForm.Hide;
     i:=Min(i,Screen.CustomFormCount)-1;
   end;
 
@@ -3062,8 +3239,11 @@
   end;
 end;
 
-function GetParentFormOrDockPanel(Control: TControl): TCustomForm;
+function GetParentFormOrDockPanel(Control: TControl; TopForm:Boolean=true): TCustomForm;
+var
+  oldControl: TControl;
 begin
+  oldControl:=Control;
   while (Control <> nil) and (Control.Parent <> nil) do
   begin
     if (Control is TAnchorDockPanel) then
@@ -3076,6 +3256,18 @@
     Result := TCustomForm(Control)
   else
     Result := nil;
+  if not TopForm then begin
+    if Control is TAnchorDockPanel then
+      exit;
+    Control:=oldControl;
+    while (Control <> nil) and (Control.Parent <> nil) do
+    begin
+      Control := Control.Parent;
+      if (Control is TCustomForm) then
+        Break;
+    end;
+    Result := TCustomForm(Control);
+  end;
 end;
 
 procedure TAnchorDockMaster.SaveMainLayoutToTree(LayoutTree: TAnchorDockLayoutTree);
@@ -3088,12 +3280,12 @@
   AFormOrDockPanel: TWinControl;
   VisibleControls: TStringList;
 
-  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean);
+  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean; AMinimized:boolean);
   begin
     // custom dock site
     LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
     LayoutNode.NodeType:=adltnCustomSite;
-    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel);
+    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel,AMinimized);
     // can have one normal dock site
     if SaveChildren then
     begin
@@ -3124,7 +3316,7 @@
       debugln(['TAnchorDockMaster.SaveMainLayoutToTree AForm=',DbgSName(AFormOrDockPanel)]);
       DebugWriteChildAnchors(AFormOrDockPanel,true,true);
       if AFormOrDockPanel is TAnchorDockPanel then begin
-        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),{false}true);
+        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),true,false);
         //LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         //TAnchorDockPanel(AFormOrDockPanel).SaveLayout(LayoutTree,LayoutNode);
       end else if AFormOrDockPanel is TAnchorDockHostSite then begin
@@ -3132,12 +3324,12 @@
         LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         Site.SaveLayout(LayoutTree,LayoutNode);
       end else if IsCustomSite(AFormOrDockPanel) then begin
-        SaveFormOrDockPanel(AFormOrDockPanel,true);
+        SaveFormOrDockPanel(AFormOrDockPanel,true,false);
       end else
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    LayoutTree.Root.Simplify(VisibleControls);
+    LayoutTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;
@@ -3157,7 +3349,7 @@
     (AControl as TAnchorDockPanel).SaveLayout(LayoutTree,LayoutTree.Root);
   end else if IsCustomSite(AControl) then begin
     LayoutTree.Root.NodeType:=adltnCustomSite;
-    LayoutTree.Root.Assign(AControl);
+    LayoutTree.Root.Assign(AControl,false,false);
     // can have one normal dock site
     Site:=TAnchorDockManager(AControl.DockManager).GetChildSite;
     if Site<>nil then begin
@@ -3252,7 +3444,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -3262,6 +3454,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -3323,6 +3516,7 @@
   HeaderFlatten                    := Settings.HeaderFlatten;
   HeaderFilled                     := Settings.HeaderFilled;
   HeaderHighlightFocused           := Settings.HeaderHighlightFocused;
+  DockSitesCanBeMinimized          := Settings.DockSitesCanBeMinimized;
 end;
 
 procedure TAnchorDockMaster.SaveSettings(Settings: TAnchorDockSettings);
@@ -3343,6 +3537,7 @@
   Settings.HeaderFlatten:=HeaderFlatten;
   Settings.HeaderFilled:=HeaderFilled;
   Settings.HeaderHighlightFocused:=HeaderHighlightFocused;
+  Settings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized;
 end;
 
 function TAnchorDockMaster.SettingsAreEqual(Settings: TAnchorDockSettings
@@ -3680,6 +3875,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -4119,6 +4315,8 @@
 end;
 
 procedure TAnchorDockHostSite.FreePages;
+var
+  i:Integer;
 begin
   FreeAndNil(FPages);
 end;
@@ -4233,6 +4431,14 @@
         akRight: NewBounds.Right:=AControl.Left+AControl.Width;
         akBottom: NewBounds.Bottom:=AControl.Top+AControl.Height;
         end;
+        if (sibling is TAnchorDockHostSite) then
+        if (sibling as TAnchorDockHostSite).FMinimized then begin
+          (sibling as TAnchorDockHostSite).FMinimized:=false;
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Parent:=(sibling as TAnchorDockHostSite);
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Visible:=True;
+          (sibling as TAnchorDockHostSite).FMinimizedControl:=nil;
+          (sibling as TAnchorDockHostSite).UpdateHeaderAlign;
+        end;
         Sibling.BoundsRect:=NewBounds;
       end;
     end;
@@ -4306,6 +4512,13 @@
       FSiteType:=adhstOneControl;
       OnlySiteLeft.Align:=alClient;
       Header.Parent:=Self;
+      if OnlySiteLeft.FMinimized then begin
+        OnlySiteLeft.FMinimized:=false;
+        OnlySiteLeft.FMinimizedControl.Parent:=OnlySiteLeft;
+        OnlySiteLeft.FMinimizedControl.Visible:=True;
+        OnlySiteLeft.FMinimizedControl:=nil;
+        UpdateHeaderAlign;
+      end;
       UpdateHeaderAlign;
 
       //debugln(['TAnchorDockHostSite.RemoveControlFromLayout.ConvertToOneControlType AFTER CONVERT "',Caption,'" to onecontrol OnlySiteLeft="',OnlySiteLeft.Caption,'"']);
@@ -4465,7 +4678,7 @@
     debugln(['TAnchorDockHostSite.Simplify ',DbgSName(Self),' ',DbgSName(AControl)]);
     if AControl is TAnchorDockHostSite then
       SimplifyOneControl
-    else if (AControl=nil) or (csDestroying in AControl.ComponentState) then
+    else if ((AControl=nil) or (csDestroying in AControl.ComponentState)) then
       DockMaster.NeedFree(Self);
   end;
 end;
@@ -4577,7 +4790,8 @@
     Result:=Controls[i];
     if Result.Owner<>Self then exit;
   end;
-  Result:=nil;
+  result:=FMinimizedControl;
+  //Result:=nil;
 end;
 
 function TAnchorDockHostSite.GetSiteCount: integer;
@@ -5165,6 +5379,105 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+begin
+  //Application.QueueAsyncCall(@AsyncMinimizeSite,0);
+  AsyncMinimizeSite(0);
+end;
+
+procedure TAnchorDockHostSite.AsyncMinimizeSite(Data: PtrInt);
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  fMinimization:=true;
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  if FMinimized then
+    AControl:=FMinimizedControl
+  else
+    AControl:=GetOneControl;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) or FMinimized then begin
+      FMinimized:=not FMinimized;
+      if FMinimized then begin
+        FMinimizedControl:=AControl;
+        AControl.Visible:=False;
+        AControl.Parent:=nil;
+      end else begin
+        AControl.Parent:=self;
+        AControl.Visible:=True;
+        FMinimizedControl:=nil;
+      end;
+      Splitter.Enabled:=AControl.Visible;
+      UpdateHeaderAlign;
+      Splitter.SetBoundsPercentually;
+    end;
+  end;
+  fMinimization:=false;
+end;
+
+procedure TAnchorDockHostSite.ShowMinimizedControl;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  SpliterRect,OverlappingFormRect:TRect;
+begin
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    SpliterRect:=Splitter.GetSpliterBoundsWithUnminimizedDockSites;
+    OverlappingFormRect:=BoundsRect;
+    case SplitterAnchorKind of
+         akTop:OverlappingFormRect.Top:=SpliterRect.Bottom;
+        akLeft:OverlappingFormRect.Left:=SpliterRect.Right;
+       akRight:OverlappingFormRect.Right:=SpliterRect.Left;
+      akBottom:OverlappingFormRect.Bottom:=SpliterRect.Top;
+    end;
+    DockMaster.FOverlappingForm:=TAnchorDockOverlappingForm.CreateNew(self);
+    DockMaster.FOverlappingForm.BoundsRect:=OverlappingFormRect;
+    DockMaster.FOverlappingForm.Parent:=GetParentFormOrDockPanel(self,false);
+    DockMaster.FOverlappingForm.AnchorDockHostSite:=self;
+    header.Parent:=DockMaster.FOverlappingForm;
+    FMinimizedControl.Parent:=DockMaster.FOverlappingForm;
+    FMinimizedControl.Show;
+    DockMaster.ShowOverlappingForm;
+  end;
+end;
+
+procedure TAnchorDockHostSite.HideMinimizedControl;
+begin
+   FMinimizedControl.Hide;
+   header.Parent:=self;
+   header.UpdateHeaderControls;
+   FMinimizedControl.Parent:=nil;
+   FreeAndNil(DockMaster.FOverlappingForm);
+end;
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5306,9 +5619,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm))and(Pages=nil);
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5362,9 +5674,33 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+const
+OppositeAlign: array[TAnchorKind] of TAlign = (
+  alBottom, // akTop,
+  alRight,  // akLeft,
+  alLeft,   // akRight,
+  alTop     // akBottom
+  );
+OppositeAnchorKindAlign: array[TAnchorKind] of TADLHeaderPosition = (
+  adlhpBottom, // akTop,
+  adlhpRight,  // akLeft,
+  adlhpLeft,   // akRight,
+  adlhpTop     // akBottom
+  );
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      NeededHeaderPosition:=OppositeAnchorKindAlign[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5390,8 +5726,11 @@
 procedure TAnchorDockHostSite.UpdateHeaderShowing;
 begin
   if Header=nil then exit;
-  if HeaderNeedsShowing then
-    Header.Parent:=Self
+  if HeaderNeedsShowing then begin
+    Header.Parent:=Self;
+    Header.MinimizeButton.Visible:=DockMaster.DockSitesCanBeMinimized;
+    Header.MinimizeButton.Parent:=Header;
+  end
   else
     Header.Parent:=nil;
 end;
@@ -5432,7 +5771,7 @@
   if (SiteType=adhstOneControl) and (OneControl<>nil)
   and (not (OneControl is TAnchorDockHostSite)) then begin
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.Name:=OneControl.Name;
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if (SiteType in [adhstLayout,adhstOneControl]) then begin
@@ -5450,7 +5789,7 @@
         Splitter.SaveLayout(ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if SiteType=adhstPages then begin
     LayoutNode.NodeType:=adltnPages;
@@ -5461,7 +5800,7 @@
         Site.SaveLayout(LayoutTree,ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else
     LayoutNode.NodeType:=adltnNone;
@@ -5476,6 +5815,9 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
+  fMinimization:=false;
+  FMinimizedControl:=Nil;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5490,13 +5832,13 @@
 end;
 
 destructor TAnchorDockHostSite.Destroy;
-//var i: Integer;
+var i: Integer;
 begin
-  //debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
-  {for i:=0 to ComponentCount-1 do
+  debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
+  for i:=0 to ComponentCount-1 do
     debugln(['TAnchorDockHostSite.Destroy Component ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   for i:=0 to ControlCount-1 do
-    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);}
+    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);
   FreePages;
   inherited Destroy;
 end;
@@ -5562,13 +5904,34 @@
 end;
 
 procedure TAnchorDockHeader.CloseButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
 begin
-  if Parent is TAnchorDockHostSite then begin
-    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(Parent),true);
-    TAnchorDockHostSite(Parent).CloseSite;
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
   end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(HeaderParent),true);
+    HeaderParent.CloseSite;
+  end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
+begin
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
+  end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    HeaderParent.MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5640,6 +6003,13 @@
       r.Right:=CloseButton.Left-1;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+1
+    else
+      r.Right:=MinimizeButton.Left-1;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,7 +6098,14 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
@@ -5735,18 +6112,67 @@
   X, Y: Integer);
 begin
   inherited MouseDown(Button, Shift, X, Y);
-  if (Button=mbLeft) and DockMaster.AllowDragging then
+  if (Button=mbLeft) and (DockMaster.AllowDragging) and (DockMaster.FOverlappingForm=nil) then
     DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
 end;
 
+procedure  TAnchorDockHeader.MouseMove(Shift: TShiftState; X,Y: Integer);
+begin
+  inherited MouseMove(Shift, X, Y);
+  if parent<>nil then
+    if parent is TAnchorDockHostSite then
+      if (parent as TAnchorDockHostSite).FMinimized then
+        if DockMaster.FOverlappingForm=nil then
+          if FMouseTimeStartX=EmptyMouseTimeStartX then
+            StartMouseNoMoveTimer(X, Y)
+          else begin
+            if (abs(FMouseTimeStartX-X)>MouseNoMoveDelta)or(abs(FMouseTimeStartY-Y)>MouseNoMoveDelta)then
+            StopMouseNoMoveTimer;
+          end;
+end;
+
+procedure TAnchorDockHeader.MouseLeave;
+begin
+  inherited;
+  StopMouseNoMoveTimer;
+end;
+
+procedure TAnchorDockHeader.StartMouseNoMoveTimer(X, Y: Integer);
+begin
+  if DockTimer.Enabled then DockTimer.Enabled:=false;
+  DockTimer.Interval:=MouseNoMoveTime;
+  DockTimer.OnTimer:=@DoMouseNoMoveTimer;
+  DockTimer.Enabled:=true;
+end;
+
+procedure TAnchorDockHeader.StopMouseNoMoveTimer;
+begin
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  DockTimer.OnTimer:=nil;
+  DockTimer.Enabled:=false;
+end;
+
+procedure TAnchorDockHeader.DoMouseNoMoveTimer(Sender: TObject);
+begin
+  StopMouseNoMoveTimer;
+  if parent<>nil then
+    if parent is TAnchorDockHostSite then
+      if (parent as TAnchorDockHostSite).FMinimized then
+        (parent as TAnchorDockHostSite).ShowMinimizedControl;
+end;
+
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alTop;
       CloseButton.Align:=alTop;
+    end;
   end else begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alRight;
       CloseButton.Align:=alRight;
+    end;
   end;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
@@ -5787,9 +6213,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,11 +6225,22 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
   PopupMenu:=DockMaster.GetPopupMenu;
   fFocused:=false;
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
 end;
 
 { TAnchorDockCloseButton }
@@ -5844,6 +6281,44 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMinButtonNormal;
+    if not IsEnabled then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonDisabled{$ELSE}twMinButtonDisabled{$ENDIF}
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonPushed{$ELSE}twMinButtonPushed{$ENDIF}
+    else
+    if FState = bsHot then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonHot{$ELSE}twMinButtonHot{$ENDIF}
+    else
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF};
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails({$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF})) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6213,6 +6688,9 @@
   ClientRectChanged:=(WidthDiff<>0) or (HeightDiff<>0);
   if ClientRectChanged or PreferredSiteSizeAsSiteMinimum then
     AlignChilds;
+  if ClientRectChanged then
+    if DockMaster.FOverlappingForm<>nil then
+      DockMaster.HideOverlappingForm(nil);
 end;
 
 procedure TAnchorDockManager.SaveToStream(Stream: TStream);
@@ -6505,32 +6983,58 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
@@ -6560,14 +7064,47 @@
   end;
 end;
 
+function TAnchorDockSplitter.GetSpliterBoundsWithUnminimizedDockSites:TRect;
+var
+  NewLeft, NewTop: Integer;
+begin
+  if ResizeAnchor in [akLeft,akRight] then
+  begin
+    if DockParentClientSize.cx> 0 then
+    begin
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+      else
+        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+      NewTop := Top;
+    end;
+  end else
+  begin
+    if DockParentClientSize.cy> 0 then
+    begin
+      NewLeft := Left;
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewTop := Round(FPercentPosition*Parent.ClientHeight)
+      else
+        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    end;
+  end;
+  result:=Rect(NewLeft,NewTop,NewLeft+Width,NewTop+Height);
+end;
+
 procedure TAnchorDockSplitter.SaveLayout(
   LayoutNode: TAnchorDockLayoutTreeNode);
+var
+  NewLeft, NewTop: Integer;
 begin
   if ResizeAnchor in [akLeft,akRight] then
     LayoutNode.NodeType:=adltnSplitterVertical
   else
     LayoutNode.NodeType:=adltnSplitterHorizontal;
-  LayoutNode.Assign(Self);
+  LayoutNode.Assign(Self,false,false);
+  if not Enabled then begin
+    LayoutNode.BoundsRect:=GetSpliterBoundsWithUnminimizedDockSites;
+  end
 end;
 
 function TAnchorDockSplitter.HasOnlyOneSibling(Side: TAnchorKind; MinPos,
@@ -6645,7 +7182,7 @@
 begin
   inherited MouseDown(Button, Shift, X, Y);
   ATabIndex := IndexOfPageAt(X, Y);
-  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) then
+  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) and (DockMaster.FOverlappingForm=nil) then
   begin
     APage:=Page[ATabIndex];
     if (APage.ControlCount>0) and (APage.Controls[0] is TAnchorDockHostSite) then
@@ -6782,6 +7319,20 @@
   PopupMenu:=DockMaster.GetPopupMenu;
 end;
 
+{ TAnchorDockOverlappingForm }
+
+constructor TAnchorDockOverlappingForm.CreateNew(AOwner: TComponent; Num: Integer = 0);
+begin
+  inherited;
+  BorderStyle:=bsNone;
+  AnchorDockHostSite:=nil;
+end;
+
+procedure TAnchorDockOverlappingForm.MouseLeave;
+begin
+  inherited;
+end;
+
 { TAnchorDockPage }
 
 procedure TAnchorDockPage.UpdateDockCaption(Exclude: TControl);
@@ -6835,9 +7386,11 @@
 
 initialization
   DockMaster:=TAnchorDockMaster.Create(nil);
+  DockTimer:=TTimer.Create(nil);
 
 finalization
   FreeAndNil(DockMaster);
+  FreeAndNil(DockTimer);
 
 end.
 
Index: components/anchordocking/anchordockoptionsdlg.lfm
===================================================================
--- components/anchordocking/anchordockoptionsdlg.lfm	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.lfm	(working copy)
@@ -1,11 +1,13 @@
 object AnchorDockOptionsFrame: TAnchorDockOptionsFrame
   Left = 0
-  Height = 482
+  Height = 567
   Top = 0
-  Width = 416
-  ClientHeight = 482
-  ClientWidth = 416
+  Width = 490
+  ClientHeight = 567
+  ClientWidth = 490
+  DesignTimePPI = 113
   OnClick = FrameClick
+  ParentFont = False
   TabOrder = 0
   DesignLeft = 513
   DesignTop = 189
@@ -12,14 +14,15 @@
   object DragThresholdLabel: TLabel
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
-    Left = 10
-    Height = 13
-    Top = 10
-    Width = 111
-    BorderSpacing.Left = 10
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 12
+    Width = 122
+    BorderSpacing.Left = 12
+    BorderSpacing.Top = 12
     Caption = 'DragThresholdLabel'
     ParentColor = False
+    ParentFont = False
   end
   object DragThresholdTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdLabel
@@ -27,15 +30,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 23
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 31
+    Width = 466
     Max = 20
     OnChange = DragThresholdTrackBarChange
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Right = 10
+    BorderSpacing.Right = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 1
@@ -46,12 +50,13 @@
     AnchorSideTop.Control = DragThresholdLabel
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
-    Left = 127
-    Height = 23
-    Top = 5
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 141
+    Height = 27
+    Top = 8
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 20
+    ParentFont = False
     TabOrder = 0
     Visible = False
   end
@@ -59,13 +64,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = DragThresholdTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 79
-    Width = 103
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 97
+    Width = 112
+    BorderSpacing.Top = 12
     Caption = 'SplitterWidthLabel'
     ParentColor = False
+    ParentFont = False
   end
   object SplitterWidthTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdTrackBar
@@ -73,14 +79,15 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 92
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 116
+    Width = 466
     Min = 1
     OnChange = SplitterWidthTrackBarChange
     Position = 1
     Anchors = [akTop, akLeft, akRight]
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 3
@@ -89,12 +96,13 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = SplitterWidthTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 142
-    Width = 160
-    BorderSpacing.Top = 4
+    Left = 12
+    Height = 23
+    Top = 175
+    Width = 169
+    BorderSpacing.Top = 5
     Caption = 'ScaleOnResizeCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 4
@@ -103,12 +111,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 166
-    Width = 149
+    Left = 12
+    Height = 23
+    Top = 198
+    Width = 160
     Caption = 'ShowHeaderCheckBox'
     OnChange = ShowHeaderCheckBoxChange
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 5
@@ -117,12 +126,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ShowHeaderCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 190
-    Width = 191
-    BorderSpacing.Left = 15
+    Left = 30
+    Height = 23
+    Top = 221
+    Width = 208
+    BorderSpacing.Left = 18
     Caption = 'ShowHeaderCaptionCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 6
@@ -131,11 +141,12 @@
     AnchorSideLeft.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 214
-    Width = 249
+    Left = 30
+    Height = 23
+    Top = 244
+    Width = 272
     Caption = 'HideHeaderCaptionForFloatingCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 7
@@ -147,15 +158,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 122
+    Left = 136
     Height = 27
-    Top = 286
-    Width = 284
+    Top = 313
+    Width = 342
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 6
-    BorderSpacing.Right = 10
-    ItemHeight = 0
+    BorderSpacing.Left = 7
+    BorderSpacing.Right = 12
+    ItemHeight = 19
     OnDrawItem = HeaderStyleComboBoxDrawItem
+    ParentFont = False
     Style = csDropDownList
     TabOrder = 10
   end
@@ -163,23 +175,25 @@
     AnchorSideLeft.Control = ShowHeaderCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrCenter
-    Left = 20
-    Height = 13
-    Top = 293
-    Width = 96
-    BorderSpacing.Left = 10
+    Left = 24
+    Height = 19
+    Top = 317
+    Width = 105
+    BorderSpacing.Left = 12
     Caption = 'HeaderStyleLabel'
     ParentColor = False
+    ParentFont = False
   end
   object FlattenHeadersCheckBox: TCheckBox
     AnchorSideLeft.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 238
-    Width = 164
+    Left = 30
+    Height = 23
+    Top = 267
+    Width = 175
     Caption = 'FlattenHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 8
@@ -188,11 +202,12 @@
     AnchorSideLeft.Control = FlattenHeadersCheckBox
     AnchorSideTop.Control = FlattenHeadersCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 262
-    Width = 154
+    Left = 30
+    Height = 23
+    Top = 290
+    Width = 164
     Caption = 'FilledHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 9
@@ -201,11 +216,12 @@
     AnchorSideLeft.Control = FilledHeadersCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 313
-    Width = 175
+    Left = 30
+    Height = 23
+    Top = 340
+    Width = 189
     Caption = 'HighlightFocusedCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 11
@@ -215,13 +231,14 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = SplitterWidthLabel
     AnchorSideTop.Side = asrCenter
-    Left = 119
-    Height = 23
-    Top = 74
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 131
+    Height = 27
+    Top = 93
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 10
     MinValue = 1
+    ParentFont = False
     TabOrder = 2
     Value = 1
     Visible = False
@@ -228,15 +245,16 @@
   end
   object HeaderAlignTopLabel: TLabel
     AnchorSideLeft.Control = DragThresholdLabel
-    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Control = DockSitesCanBeMinimized
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 347
-    Width = 117
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 398
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignTopLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignTopTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -244,10 +262,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 360
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 417
+    Width = 466
     Frequency = 10
     Max = 150
     OnChange = HeaderAlignTopTrackBarChange
@@ -254,7 +272,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 13
@@ -264,12 +283,13 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignTopLabel
     AnchorSideTop.Side = asrCenter
-    Left = 133
-    Height = 23
-    Top = 342
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 394
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 150
+    ParentFont = False
     TabOrder = 12
     Visible = False
   end
@@ -277,13 +297,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = HeaderAlignTopTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 417
-    Width = 120
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 484
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignLeftLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignLeftTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -291,10 +312,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 430
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 503
+    Width = 466
     Frequency = 10
     Max = 200
     OnChange = HeaderAlignLeftTrackBarChange
@@ -301,7 +322,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 15
@@ -311,13 +333,28 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignLeftLabel
     AnchorSideTop.Side = asrCenter
-    Left = 136
-    Height = 23
-    Top = 412
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 480
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 200
+    ParentFont = False
     TabOrder = 14
     Visible = False
   end
+  object DockSitesCanBeMinimized: TCheckBox
+    AnchorSideLeft.Control = FilledHeadersCheckBox
+    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Side = asrBottom
+    Left = 30
+    Height = 23
+    Top = 363
+    Width = 185
+    Caption = 'DockSitesCanBeMinimized'
+    ParentFont = False
+    ParentShowHint = False
+    ShowHint = True
+    TabOrder = 16
+  end
 end
Index: components/anchordocking/anchordockoptionsdlg.pas
===================================================================
--- components/anchordocking/anchordockoptionsdlg.pas	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.pas	(working copy)
@@ -37,6 +37,7 @@
     HeaderStyleLabel: TLabel;
     HideHeaderCaptionForFloatingCheckBox: TCheckBox;
     HighlightFocusedCheckBox: TCheckBox;
+    DockSitesCanBeMinimized: TCheckBox;
     ScaleOnResizeCheckBox: TCheckBox;
     ShowHeaderCaptionCheckBox: TCheckBox;
     ShowHeaderCheckBox: TCheckBox;
@@ -299,6 +300,7 @@
   HeaderStyleLabel.Enabled:=HasHeaders;
   HeaderStyleComboBox.Enabled:=HasHeaders;
   HighlightFocusedCheckBox.Enabled:=HasHeaders;
+  DockSitesCanBeMinimized.Enabled:=HasHeaders;
 end;
 
 constructor TAnchorDockOptionsFrame.Create(TheOwner: TComponent);
@@ -356,6 +358,7 @@
   TheSettings.HeaderFilled:=FilledHeadersCheckBox.Checked;
   TheSettings.HeaderStyle:=TADHeaderStyle(HeaderStyleComboBox.ItemIndex);
   TheSettings.HeaderHighlightFocused:=HighlightFocusedCheckBox.Checked;
+  TheSettings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized.Checked;
 end;
 
 procedure TAnchorDockOptionsFrame.LoadFromSettings(
@@ -429,6 +432,10 @@
   HighlightFocusedCheckBox.Checked:=TheSettings.HeaderHighlightFocused;
   HighlightFocusedCheckBox.Caption:=adrsHighlightFocused;
   HighlightFocusedCheckBox.Hint:=adrsHighlightFocusedHint;
+
+  DockSitesCanBeMinimized.Checked:=TheSettings.DockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Caption:=adrsDockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Hint:=adrsDockSitesCanBeMinimizedHint;
 end;
 
 end.
Index: components/anchordocking/anchordockpanel.pas
===================================================================
--- components/anchordocking/anchordockpanel.pas	(revision 59428)
+++ components/anchordocking/anchordockpanel.pas	(working copy)
@@ -55,7 +55,7 @@
   begin
 
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,false);
     LayoutNode.Name:={OneControl.}Name;
 
     TAnchorDockHostSite(OneControl).SaveLayout(LayoutTree,LayoutNode);
Index: components/anchordocking/anchordockstorage.pas
===================================================================
--- components/anchordocking/anchordockstorage.pas	(revision 59428)
+++ components/anchordocking/anchordockstorage.pas	(working copy)
@@ -64,6 +64,7 @@
     FTabPosition: TTabPosition;
     FWindowState: TWindowState;
     FControlLocation: TADLControlLocation;
+    FMinimized: Boolean;
     function GetAnchors(Site: TAnchorKind): string;
     function GetBottom: integer;
     function GetHeight: integer;
@@ -90,6 +91,7 @@
     procedure SetTop(const AValue: integer);
     procedure SetWidth(const AValue: integer);
     procedure SetWindowState(const AValue: TWindowState);
+    procedure SetMinimized(const AValue: boolean);
   public
     constructor Create;
     destructor Destroy; override;
@@ -96,7 +98,7 @@
     procedure Clear;
     function IsEqual(Node: TAnchorDockLayoutTreeNode): boolean;
     procedure Assign(Node: TAnchorDockLayoutTreeNode); overload;
-    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean=false); overload;
+    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean); overload;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
     procedure LoadFromConfig(Path: string; Config: TRttiXMLConfig); overload;
     procedure SaveToConfig(Config: TConfigStorage); overload;
@@ -106,7 +108,7 @@
     procedure CheckConsistency; virtual;
 
     // simplifying
-    procedure Simplify(ExistingNames: TStrings);
+    procedure Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
     procedure DeleteNode(ChildNode: TAnchorDockLayoutTreeNode);
     function FindNodeBoundSplitter(ChildNode: TAnchorDockLayoutTreeNode;
                                    Side: TAnchorKind): TAnchorDockLayoutTreeNode;
@@ -135,6 +137,7 @@
     property Monitor: integer read FMonitor write SetMonitor;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property TabPosition: TTabPosition read FTabPosition write SetTabPosition;
+    property Minimized: Boolean read FMinimized write SetMinimized;
     function Count: integer;
     function IsSplitter: boolean;
     function IsRootWindow: boolean;
@@ -988,6 +991,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockLayoutTreeNode.SetMinimized(const AValue: boolean);
+begin
+  if FMinimized=AValue then exit;
+  FMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockLayoutTreeNode.SetTop(const AValue: integer);
 begin
   if Top=AValue then exit;
@@ -1084,6 +1094,7 @@
   BoundSplitterPos:=Node.BoundSplitterPos;
   WorkAreaRect:=Node.WorkAreaRect;
   Monitor:=Node.Monitor;
+  Minimized:=Node.Minimized;
   for a:=low(TAnchorKind) to high(TAnchorKind) do
     Anchors[a]:=Node.Anchors[a];
   while Count>Node.Count do Nodes[Count-1].Free;
@@ -1098,9 +1109,10 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean=false);
+procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean);
 var
   AnchorControl: TControl;
+  ParentForm:TCustomForm;
   a: TAnchorKind;
 begin
   Name:=AControl.Name;
@@ -1109,12 +1121,18 @@
   else
     BoundsRect:=AControl.BoundsRect;
   Align:=AControl.Align;
+  Minimized:=AMinimized;
   if (AControl.Parent=nil) and (AControl is TCustomForm) then begin
     WindowState:=TCustomForm(AControl).WindowState;
     Monitor:=TCustomForm(AControl).Monitor.MonitorNum;
     WorkAreaRect:=TCustomForm(AControl).Monitor.WorkareaRect;
-  end else
-    WindowState:=GetParentForm(AControl).WindowState;
+  end else begin
+    ParentForm:=GetParentForm(AControl);
+    if assigned(ParentForm) then
+      WindowState:=ParentForm.WindowState
+    else
+      WindowState:=wsNormal;
+  end;
   if AControl is TCustomTabControl then
     TabPosition:=TCustomTabControl(AControl).TabPosition
   else
@@ -1137,6 +1155,7 @@
   Clear;
   Name:=Config.GetValue('Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue('Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue('Minimized',false);
   Left:=Config.GetValue('Bounds/Left',0);
   Top:=Config.GetValue('Bounds/Top',0);
   Width:=Config.GetValue('Bounds/Width',0);
@@ -1171,6 +1190,7 @@
   Clear;
   Name:=Config.GetValue(Path+'Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue(Path+'Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue(Path+'Minimized',false);
   Left:=Config.GetValue(Path+'Bounds/Left',0);
   Top:=Config.GetValue(Path+'Bounds/Top',0);
   Width:=Config.GetValue(Path+'Bounds/Width',0);
@@ -1219,6 +1239,7 @@
                                           ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue('Header/TabPosition',ADLTabPostionNames[TabPosition],
                                              ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue('Minimized',Minimized,False);
   Config.SetDeleteValue('Monitor',Monitor,0);
   Config.SetDeleteValue('ChildCount',Count,0);
   for i:=1 to Count do begin
@@ -1252,6 +1273,7 @@
                                                ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue(Path+'Header/TabPosition',ADLTabPostionNames[TabPosition],
                                                   ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue(Path+'Minimized',Minimized,False);
   Config.SetDeleteValue(Path+'Monitor',Monitor,0);
   Config.SetDeleteValue(Path+'ChildCount',Count,0);
   for i:=1 to Count do
@@ -1397,7 +1419,7 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings);
+procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
 { Simplification rules:
    1. Control nodes without existing name are deleted.
    2. Empty layouts and pages are deleted
@@ -1406,16 +1428,18 @@
 var
   i: Integer;
   ChildNode: TAnchorDockLayoutTreeNode;
+  NodeMinimized:boolean;
 begin
   // simplify children
   i:=Count-1;
   while i>=0 do begin
     ChildNode:=Nodes[i];
-    ChildNode.Simplify(ExistingNames);
+    NodeMinimized:=ParentMinimized or ChildNode.Minimized;
+    ChildNode.Simplify(ExistingNames,NodeMinimized);
 
     if (ChildNode.NodeType=adltnControl) then begin
       // leaf node => check if there is a control
-      if (ChildNode.Name='') or (ExistingNames.IndexOf(ChildNode.Name)<0) then
+      if (ChildNode.Name='') or ((ExistingNames.IndexOf(ChildNode.Name)<0) and (not NodeMinimized)) then
         DeleteNode(ChildNode);
     end else if ChildNode.IsSplitter then begin
       // splitter
@@ -1424,7 +1448,7 @@
         ChildNode[0].Free;
     end else if ChildNode.NodeType=adltnCustomSite then begin
       // custom dock site
-    end else if ChildNode.Count=0 then begin
+    end else if (ChildNode.Count=0)and(not NodeMinimized) then begin
       // inner node without child => delete
       DeleteNode(ChildNode);
     end else if (ChildNode.Count=1)
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59428)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';
@@ -82,6 +83,8 @@
   adrsFilledHeadersHint = 'Fill headers of docked controls';
   adrsHighlightFocused = 'Highlight focused';
   adrsHighlightFocusedHint = 'Highlight header of focused docked control';
+  adrsDockSitesCanBeMinimized = 'Dock sites can be minimized';
+  adrsDockSitesCanBeMinimizedHint = 'Dock sites can be minimized';
 
 implementation
 
Index: components/anchordocking/design/anchordesktopoptions.pas
===================================================================
--- components/anchordocking/design/anchordesktopoptions.pas	(revision 59428)
+++ components/anchordocking/design/anchordesktopoptions.pas	(working copy)
@@ -272,7 +272,7 @@
         // custom dock site
         LayoutNode:=FTree.NewNode(FTree.Root);
         LayoutNode.NodeType:=adltnCustomSite;
-        LayoutNode.Assign(AForm);
+        LayoutNode.Assign(AForm,false,false);
         // can have one normal dock site
         Site:=TAnchorDockManager(AForm.DockManager).GetChildSite;
         if Site<>nil then begin
@@ -287,7 +287,7 @@
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    FTree.Root.Simplify(VisibleControls);
+    FTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59428)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -109,6 +109,11 @@
 const ADAutoSizingReason = 'TAnchorDockMaster Delayed';
 {$ENDIF}
 
+const EmptyMouseTimeStartX=low(Integer);
+      MouseNoMoveDelta=5;
+      MouseNoMoveTime=500;
+      HideOverlappingFormByMouseLoseTime=500;
+
 type
   TAnchorDockHostSite = class;
 
@@ -123,6 +128,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +146,12 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
+    FMouseTimeStartX,FMouseTimeStartY:Integer;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -147,6 +163,11 @@
           PreferredHeight: integer; WithThemeSpace: Boolean); override;
     procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X,
              Y: Integer); override;
+    procedure MouseMove(Shift: TShiftState; X,Y: Integer); override;
+    procedure MouseLeave;  override;
+    procedure StartMouseNoMoveTimer(X, Y: Integer);
+    procedure StopMouseNoMoveTimer;
+    procedure DoMouseNoMoveTimer(Sender: TObject);
     procedure UpdateHeaderControls;
     procedure SetAlign(Value: TAlign); override;
     procedure DoOnShowHint(HintInfo: PHintInfo); override;
@@ -154,6 +175,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -190,6 +212,7 @@
     procedure SetBoundsKeepDockBounds(ALeft, ATop, AWidth, AHeight: integer); // movement for scaling keeps the DockBounds
     function SideAnchoredControlCount(Side: TAnchorKind): integer;
     function HasAnchoredControls: boolean;
+    function GetSpliterBoundsWithUnminimizedDockSites:TRect;
     procedure SaveLayout(LayoutNode: TAnchorDockLayoutTreeNode);
     function HasOnlyOneSibling(Side: TAnchorKind; MinPos, MaxPos: integer): TControl;
     property DockRestoreBounds: TRect read FDockRestoreBounds write FDockRestoreBounds;
@@ -241,6 +264,15 @@
   end;
   TAnchorDockPageControlClass = class of TAnchorDockPageControl;
 
+
+  TAnchorDockOverlappingForm = class(TCustomForm)
+  protected
+    procedure MouseLeave;  override;
+  public
+    AnchorDockHostSite:TAnchorDockHostSite;
+    constructor CreateNew(AOwner: TComponent; Num: Integer = 0); override;
+  end;
+
   { TAnchorDockHostSite
     This form is the dockhostsite for all controls.
     When docked together they build a tree structure with the docked controls
@@ -262,7 +294,10 @@
     FPages: TAnchorDockPageControl;
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
-    fUpdateLayout: integer;
+    fUpdateLayout: Integer;
+    FMinimized: Boolean;
+    fMinimization: Boolean;
+    FMinimizedControl: TControl;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +354,10 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
+    procedure AsyncMinimizeSite(Data: PtrInt);
+    procedure ShowMinimizedControl;
+    procedure HideMinimizedControl;
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -431,6 +470,7 @@
     FShowHeader: boolean;
     FShowHeaderCaption: boolean;
     FSplitterWidth: integer;
+    FDockSitecCanBeMinimized: boolean;
     procedure SetAllowDragging(AValue: boolean);
     procedure SetDockOutsideMargin(AValue: integer);
     procedure SetDockParentMargin(AValue: integer);
@@ -448,6 +488,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitecCanBeMinimized(AValue: boolean);
   public
     property DragTreshold: integer read FDragTreshold write SetDragTreshold;
     property DockOutsideMargin: integer read FDockOutsideMargin write SetDockOutsideMargin;
@@ -466,6 +507,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused;
+    property DockSitesCanBeMinimized: boolean read FDockSitecCanBeMinimized write SetDockSitecCanBeMinimized;
     procedure IncreaseChangeStamp; inline;
     property ChangeStamp: integer read FChangeStamp;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
@@ -502,6 +544,7 @@
     FHeaderFlatten: boolean;
     FHeaderFilled: boolean;
     FHeaderHighlightFocused: boolean;
+    FDockSitesCanBeMinimized: boolean;
     FIdleConnected: Boolean;
     FManagerClass: TAnchorDockManagerClass;
     FOnCreateControl: TADCreateControlEvent;
@@ -531,6 +574,7 @@
     fPopupMenu: TPopupMenu;
     // Used by RestoreLayout:
     WorkArea, SrcWorkArea: TRect;
+    FOverlappingForm:TAnchorDockOverlappingForm;
 
     function GetControls(Index: integer): TControl;
     function GetLocalizedHeaderHint: string;
@@ -541,6 +585,8 @@
     function GetNodeSite(Node: TAnchorDockLayoutTreeNode): TAnchorDockHostSite;
     procedure MapTreeToControls(Tree: TAnchorDockLayoutTree);
     function RestoreLayout(Tree: TAnchorDockLayoutTree; Scale: boolean): boolean;
+    procedure SetMinimizedState(Tree: TAnchorDockLayoutTree);
+    procedure SetnodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
     procedure EnableAllAutoSizing;
     procedure ClearLayoutProperties(AControl: TControl; NewAlign: TAlign = alClient);
     procedure PopupMenuPopup(Sender: TObject);
@@ -561,6 +607,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitesCanBeMinimized(AValue: boolean);
 
     procedure SetShowMenuItemShowHeader(AValue: boolean);
     procedure SetupSite(Site: TWinControl; ANode: TAnchorDockLayoutTreeNode;
@@ -584,8 +631,12 @@
     procedure SetHideHeaderCaptionFloatingControl(const AValue: boolean);
     procedure SetSplitterWidth(const AValue: integer);
     procedure OnIdle(Sender: TObject; var Done: Boolean);
+    procedure StartHideOverlappingTimer;
+    procedure StopHideOverlappingTimer;
     procedure AsyncSimplify({%H-}Data: PtrInt);
   public
+    procedure ShowOverlappingForm;
+    procedure HideOverlappingForm(Sender: TObject);
     constructor Create(AOwner: TComponent); override;
     destructor Destroy; override;
     function FullRestoreLayout(Tree: TAnchorDockLayoutTree; Scale: Boolean): Boolean;
@@ -680,6 +731,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten default true;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled default true;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused default false;
+    property DockSitesCanBeMinimized: boolean read FDockSitesCanBeMinimized write SetDockSitesCanBeMinimized default false;
 
     property SplitterWidth: integer read FSplitterWidth write SetSplitterWidth default 4;
     property ScaleOnResize: boolean read FScaleOnResize write SetScaleOnResize default true; // scale children when resizing a site
@@ -698,6 +750,7 @@
 
 var
   DockMaster: TAnchorDockMaster = nil;
+  DockTimer: TTimer = nil;
 
 const
   ADHeaderStyleNames: array[TADHeaderStyle] of string = (
@@ -970,6 +1023,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -1361,6 +1435,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockSettings.SetDockSitecCanBeMinimized(AValue: boolean);
+begin
+  if FDockSitecCanBeMinimized=AValue then Exit;
+  FDockSitecCanBeMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockSettings.Assign(Source: TAnchorDockSettings);
 begin
   FAllowDragging := Source.FAllowDragging;
@@ -1381,6 +1462,7 @@
   FShowHeaderCaption := Source.FShowHeaderCaption;
   FSplitterWidth := Source.FSplitterWidth;
   FHeaderHighlightFocused:=Source.FHeaderHighlightFocused;
+  FDockSitecCanBeMinimized:=Source.FDockSitecCanBeMinimized;
 end;
 
 procedure TAnchorDockSettings.IncreaseChangeStamp;
@@ -1407,6 +1489,7 @@
   HeaderFlatten:=Config.GetValue('HeaderFlatten',true);
   HeaderFilled:=Config.GetValue('HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue('HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue('DockSitecCanBeMinimized',False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1429,6 +1512,7 @@
   Config.SetDeleteValue(Path+'HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue(Path+'HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue(Path+'HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue(Path+'DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
 end;
 
 procedure TAnchorDockSettings.SaveToConfig(Config: TConfigStorage);
@@ -1450,6 +1534,7 @@
   Config.SetDeleteValue('HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue('HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue('HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue('DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1472,6 +1557,7 @@
       and (HeaderFlatten=Settings.HeaderFlatten)
       and (HeaderFilled=Settings.HeaderFilled)
       and (HeaderHighlightFocused=Settings.HeaderHighlightFocused)
+      and (DockSitesCanBeMinimized=Settings.DockSitesCanBeMinimized)
       ;
 end;
 
@@ -1494,6 +1580,7 @@
   HeaderFlatten:=Config.GetValue(Path+'HeaderFlatten',true);
   HeaderFilled:=Config.GetValue(Path+'HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue(Path+'HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue(Path+'DockSitecCanBeMinimized',False);
 end;
 
 { TAnchorDockMaster }
@@ -2021,6 +2108,8 @@
     aHostSite:=TAnchorDockHostSite(Site);
     aHostSite.Header.HeaderPosition:=ANode.HeaderPosition;
     aHostSite.DockRestoreBounds:=NewBounds;
+    //aHostSite.FMinimized:=ANode.Minimized;
+    //we update aHostSite.FMinimized in TAnchorDockMaster.SetMinimizedState
     if (ANode.NodeType<>adltnPages) and (aHostSite.Pages<>nil) then
       aHostSite.FreePages;
   end;
@@ -2040,6 +2129,25 @@
   fTreeNameToDocker[Node.Name]:=Result;
 end;
 
+procedure TAnchorDockMaster.SetNodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
+var
+  HostSite:TAnchorDockHostSite;
+  i:integer;
+begin
+  HostSite:=GetNodeSite(ANode);
+  if Assigned(HostSite) then
+    if HostSite.FMinimized<>ANode.Minimized then
+      Application.QueueAsyncCall(@HostSite.AsyncMinimizeSite,0);
+      //HostSite.MinimizeSite;
+  for i:=0 to ANode.Count-1 do
+    SetnodeMinimizedState(ANode.Nodes[i]);
+end;
+
+procedure TAnchorDockMaster.SetMinimizedState(Tree: TAnchorDockLayoutTree);
+begin
+  SetnodeMinimizedState(Tree.Root);
+end;
+
 function TAnchorDockMaster.RestoreLayout(Tree: TAnchorDockLayoutTree;
   Scale: boolean): boolean;
 
@@ -2193,7 +2301,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -2358,7 +2466,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -2368,6 +2476,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -2422,11 +2531,54 @@
   OptionsChanged;
 end;
 
+procedure TAnchorDockMaster.StartHideOverlappingTimer;
+begin
+  if not DockTimer.Enabled then begin
+    DockTimer.Interval:=HideOverlappingFormByMouseLoseTime;
+    DockTimer.OnTimer:=@HideOverlappingForm;
+    DockTimer.Enabled:=true;
+  end;
+end;
+
+procedure TAnchorDockMaster.StopHideOverlappingTimer;
+begin
+  DockTimer.Enabled:=False;
+  DockTimer.Interval:=0;
+  DockTimer.OnTimer:=nil;
+end;
+
+function IsParentControl(aParent, aControl: TControl): boolean;
+begin
+  while (aControl <> nil) and (aControl.Parent <> nil) do
+  begin
+    if (aControl=aParent) then
+      exit(true);
+    aControl := aControl.Parent;
+  end;
+  result:=aControl=aParent;
+end;
+
+
 procedure TAnchorDockMaster.OnIdle(Sender: TObject; var Done: Boolean);
+var
+  MousePos: TPoint;
+  Bounds:Trect;
 begin
   if Done then ;
-  IdleConnected:=false;
   Restoring:=false;
+  if FOverlappingForm=nil then
+    IdleConnected:=false
+  else begin
+    GetCursorPos(MousePos);
+    Bounds.TopLeft:=FOverlappingForm.ClientToScreen(point(0,0));
+    Bounds.BottomRight:=FOverlappingForm.ClientToScreen(point(FOverlappingForm.Width,FOverlappingForm.Height));
+    if not IsParentControl(FOverlappingForm, GetCaptureControl) then begin
+      if not PtInRect(Bounds,MousePos) then
+          StartHideOverlappingTimer
+        else
+          StopHideOverlappingTimer;
+    end;
+  end;
 end;
 
 procedure TAnchorDockMaster.AsyncSimplify(Data: PtrInt);
@@ -2514,6 +2666,24 @@
   InvalidateHeaders;
 end;
 
+procedure TAnchorDockMaster.SetDockSitesCanBeMinimized(AValue: boolean);
+var
+  i:integer;
+  Site: TAnchorDockHostSite;
+begin
+  if FDockSitesCanBeMinimized=AValue then Exit;
+  FDockSitesCanBeMinimized:=AValue;
+  for i:=0 to ComponentCount-1 do begin
+    Site:=TAnchorDockHostSite(Components[i]);
+    if not (Site is TAnchorDockHostSite) then continue;
+    if (Site.Header<>nil) then begin
+      DisableControlAutoSizing(Site);
+      Site.UpdateHeaderShowing;
+    end;
+  end;
+  EnableAllAutoSizing;
+  OptionsChanged;
+end;
 procedure TAnchorDockMaster.SetScaleOnResize(AValue: boolean);
 begin
   if FScaleOnResize=AValue then Exit;
@@ -2668,6 +2838,20 @@
     EnableAllAutoSizing;
 end;
 
+procedure TAnchorDockMaster.ShowOverlappingForm;
+begin
+  FOverlappingForm.Show;
+  IdleConnected:=true;
+end;
+
+procedure TAnchorDockMaster.HideOverlappingForm(Sender: TObject);
+begin
+  StopHideOverlappingTimer;
+  FOverlappingForm.Hide;
+  FOverlappingForm.AnchorDockHostSite.HideMinimizedControl;
+  IdleConnected:=false;
+end;
+
 constructor TAnchorDockMaster.Create(AOwner: TComponent);
 begin
   inherited Create(AOwner);
@@ -2698,14 +2882,14 @@
   FPageClass:=TAnchorDockPage;
   FRestoreLayouts:=TAnchorDockRestoreLayouts.Create;
   FHeaderHighlightFocused:=false;
+  FDockSitesCanBeMinimized:=false;
+  FOverlappingForm:=nil;
 end;
 
 destructor TAnchorDockMaster.Destroy;
 var
   AControl: TControl;
-  {$IFDEF VerboseAnchorDocking}
-  i: Integer;
-  {$ENDIF}
+  i, j: Integer;
 begin
   QueueSimplify:=false;
   FreeAndNil(FRestoreLayouts);
@@ -2727,6 +2911,12 @@
     debugln(['TAnchorDockMaster.Destroy ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   end;
   {$ENDIF}
+  for i:=0 to ComponentCount-1 do begin
+    for j:=0 to ComponentCount-1 do begin
+      if i<>j then
+        TControl(Components[i]).RemoveAllHandlersOfObject(TControl(Components[j]));
+  end;
+  end;
   inherited Destroy;
 end;
 
@@ -3018,7 +3208,8 @@
   i:=Screen.CustomFormCount-1;
   while i>=0 do begin
     AForm:=GetParentForm(Screen.CustomForms[i]);
-    AForm.Hide;
+    if Assigned(AForm)then
+      AForm.Hide;
     i:=Min(i,Screen.CustomFormCount)-1;
   end;
 
@@ -3062,8 +3253,11 @@
   end;
 end;
 
-function GetParentFormOrDockPanel(Control: TControl): TCustomForm;
+function GetParentFormOrDockPanel(Control: TControl; TopForm:Boolean=true): TCustomForm;
+var
+  oldControl: TControl;
 begin
+  oldControl:=Control;
   while (Control <> nil) and (Control.Parent <> nil) do
   begin
     if (Control is TAnchorDockPanel) then
@@ -3076,6 +3270,18 @@
     Result := TCustomForm(Control)
   else
     Result := nil;
+  if not TopForm then begin
+    if Control is TAnchorDockPanel then
+      exit;
+    Control:=oldControl;
+    while (Control <> nil) and (Control.Parent <> nil) do
+    begin
+      Control := Control.Parent;
+      if (Control is TCustomForm) then
+        Break;
+    end;
+    Result := TCustomForm(Control);
+  end;
 end;
 
 procedure TAnchorDockMaster.SaveMainLayoutToTree(LayoutTree: TAnchorDockLayoutTree);
@@ -3088,12 +3294,12 @@
   AFormOrDockPanel: TWinControl;
   VisibleControls: TStringList;
 
-  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean);
+  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean; AMinimized:boolean);
   begin
     // custom dock site
     LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
     LayoutNode.NodeType:=adltnCustomSite;
-    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel);
+    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel,AMinimized);
     // can have one normal dock site
     if SaveChildren then
     begin
@@ -3124,7 +3330,7 @@
       debugln(['TAnchorDockMaster.SaveMainLayoutToTree AForm=',DbgSName(AFormOrDockPanel)]);
       DebugWriteChildAnchors(AFormOrDockPanel,true,true);
       if AFormOrDockPanel is TAnchorDockPanel then begin
-        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),{false}true);
+        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),true,false);
         //LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         //TAnchorDockPanel(AFormOrDockPanel).SaveLayout(LayoutTree,LayoutNode);
       end else if AFormOrDockPanel is TAnchorDockHostSite then begin
@@ -3132,12 +3338,12 @@
         LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         Site.SaveLayout(LayoutTree,LayoutNode);
       end else if IsCustomSite(AFormOrDockPanel) then begin
-        SaveFormOrDockPanel(AFormOrDockPanel,true);
+        SaveFormOrDockPanel(AFormOrDockPanel,true,false);
       end else
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    LayoutTree.Root.Simplify(VisibleControls);
+    LayoutTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;
@@ -3157,7 +3363,7 @@
     (AControl as TAnchorDockPanel).SaveLayout(LayoutTree,LayoutTree.Root);
   end else if IsCustomSite(AControl) then begin
     LayoutTree.Root.NodeType:=adltnCustomSite;
-    LayoutTree.Root.Assign(AControl);
+    LayoutTree.Root.Assign(AControl,false,false);
     // can have one normal dock site
     Site:=TAnchorDockManager(AControl.DockManager).GetChildSite;
     if Site<>nil then begin
@@ -3252,7 +3458,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -3262,6 +3468,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -3323,6 +3530,7 @@
   HeaderFlatten                    := Settings.HeaderFlatten;
   HeaderFilled                     := Settings.HeaderFilled;
   HeaderHighlightFocused           := Settings.HeaderHighlightFocused;
+  DockSitesCanBeMinimized          := Settings.DockSitesCanBeMinimized;
 end;
 
 procedure TAnchorDockMaster.SaveSettings(Settings: TAnchorDockSettings);
@@ -3343,6 +3551,7 @@
   Settings.HeaderFlatten:=HeaderFlatten;
   Settings.HeaderFilled:=HeaderFilled;
   Settings.HeaderHighlightFocused:=HeaderHighlightFocused;
+  Settings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized;
 end;
 
 function TAnchorDockMaster.SettingsAreEqual(Settings: TAnchorDockSettings
@@ -3680,6 +3889,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -4119,6 +4329,8 @@
 end;
 
 procedure TAnchorDockHostSite.FreePages;
+var
+  i:Integer;
 begin
   FreeAndNil(FPages);
 end;
@@ -4233,6 +4445,14 @@
         akRight: NewBounds.Right:=AControl.Left+AControl.Width;
         akBottom: NewBounds.Bottom:=AControl.Top+AControl.Height;
         end;
+        if (sibling is TAnchorDockHostSite) then
+        if (sibling as TAnchorDockHostSite).FMinimized then begin
+          (sibling as TAnchorDockHostSite).FMinimized:=false;
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Parent:=(sibling as TAnchorDockHostSite);
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Visible:=True;
+          (sibling as TAnchorDockHostSite).FMinimizedControl:=nil;
+          (sibling as TAnchorDockHostSite).UpdateHeaderAlign;
+        end;
         Sibling.BoundsRect:=NewBounds;
       end;
     end;
@@ -4306,6 +4526,13 @@
       FSiteType:=adhstOneControl;
       OnlySiteLeft.Align:=alClient;
       Header.Parent:=Self;
+      if OnlySiteLeft.FMinimized then begin
+        OnlySiteLeft.FMinimized:=false;
+        OnlySiteLeft.FMinimizedControl.Parent:=OnlySiteLeft;
+        OnlySiteLeft.FMinimizedControl.Visible:=True;
+        OnlySiteLeft.FMinimizedControl:=nil;
+        UpdateHeaderAlign;
+      end;
       UpdateHeaderAlign;
 
       //debugln(['TAnchorDockHostSite.RemoveControlFromLayout.ConvertToOneControlType AFTER CONVERT "',Caption,'" to onecontrol OnlySiteLeft="',OnlySiteLeft.Caption,'"']);
@@ -4465,7 +4692,7 @@
     debugln(['TAnchorDockHostSite.Simplify ',DbgSName(Self),' ',DbgSName(AControl)]);
     if AControl is TAnchorDockHostSite then
       SimplifyOneControl
-    else if (AControl=nil) or (csDestroying in AControl.ComponentState) then
+    else if ((AControl=nil) or (csDestroying in AControl.ComponentState)) then
       DockMaster.NeedFree(Self);
   end;
 end;
@@ -4577,7 +4804,8 @@
     Result:=Controls[i];
     if Result.Owner<>Self then exit;
   end;
-  Result:=nil;
+  result:=FMinimizedControl;
+  //Result:=nil;
 end;
 
 function TAnchorDockHostSite.GetSiteCount: integer;
@@ -5165,6 +5393,105 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+begin
+  //Application.QueueAsyncCall(@AsyncMinimizeSite,0);
+  AsyncMinimizeSite(0);
+end;
+
+procedure TAnchorDockHostSite.AsyncMinimizeSite(Data: PtrInt);
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  fMinimization:=true;
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  if FMinimized then
+    AControl:=FMinimizedControl
+  else
+    AControl:=GetOneControl;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) or FMinimized then begin
+      FMinimized:=not FMinimized;
+      if FMinimized then begin
+        FMinimizedControl:=AControl;
+        AControl.Visible:=False;
+        AControl.Parent:=nil;
+      end else begin
+        AControl.Parent:=self;
+        AControl.Visible:=True;
+        FMinimizedControl:=nil;
+      end;
+      Splitter.Enabled:=AControl.Visible;
+      UpdateHeaderAlign;
+      Splitter.SetBoundsPercentually;
+    end;
+  end;
+  fMinimization:=false;
+end;
+
+procedure TAnchorDockHostSite.ShowMinimizedControl;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  SpliterRect,OverlappingFormRect:TRect;
+begin
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    SpliterRect:=Splitter.GetSpliterBoundsWithUnminimizedDockSites;
+    OverlappingFormRect:=BoundsRect;
+    case SplitterAnchorKind of
+         akTop:OverlappingFormRect.Top:=SpliterRect.Bottom;
+        akLeft:OverlappingFormRect.Left:=SpliterRect.Right;
+       akRight:OverlappingFormRect.Right:=SpliterRect.Left;
+      akBottom:OverlappingFormRect.Bottom:=SpliterRect.Top;
+    end;
+    DockMaster.FOverlappingForm:=TAnchorDockOverlappingForm.CreateNew(self);
+    DockMaster.FOverlappingForm.BoundsRect:=OverlappingFormRect;
+    DockMaster.FOverlappingForm.Parent:=GetParentFormOrDockPanel(self,false);
+    DockMaster.FOverlappingForm.AnchorDockHostSite:=self;
+    header.Parent:=DockMaster.FOverlappingForm;
+    FMinimizedControl.Parent:=DockMaster.FOverlappingForm;
+    FMinimizedControl.Show;
+    DockMaster.ShowOverlappingForm;
+  end;
+end;
+
+procedure TAnchorDockHostSite.HideMinimizedControl;
+begin
+   FMinimizedControl.Hide;
+   header.Parent:=self;
+   header.UpdateHeaderControls;
+   FMinimizedControl.Parent:=nil;
+   FreeAndNil(DockMaster.FOverlappingForm);
+end;
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5306,9 +5633,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm))and(Pages=nil);
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5362,9 +5688,33 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+const
+OppositeAlign: array[TAnchorKind] of TAlign = (
+  alBottom, // akTop,
+  alRight,  // akLeft,
+  alLeft,   // akRight,
+  alTop     // akBottom
+  );
+OppositeAnchorKindAlign: array[TAnchorKind] of TADLHeaderPosition = (
+  adlhpBottom, // akTop,
+  adlhpRight,  // akLeft,
+  adlhpLeft,   // akRight,
+  adlhpTop     // akBottom
+  );
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      NeededHeaderPosition:=OppositeAnchorKindAlign[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5390,8 +5740,11 @@
 procedure TAnchorDockHostSite.UpdateHeaderShowing;
 begin
   if Header=nil then exit;
-  if HeaderNeedsShowing then
-    Header.Parent:=Self
+  if HeaderNeedsShowing then begin
+    Header.Parent:=Self;
+    Header.MinimizeButton.Visible:=DockMaster.DockSitesCanBeMinimized;
+    Header.MinimizeButton.Parent:=Header;
+  end
   else
     Header.Parent:=nil;
 end;
@@ -5432,7 +5785,7 @@
   if (SiteType=adhstOneControl) and (OneControl<>nil)
   and (not (OneControl is TAnchorDockHostSite)) then begin
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.Name:=OneControl.Name;
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if (SiteType in [adhstLayout,adhstOneControl]) then begin
@@ -5450,7 +5803,7 @@
         Splitter.SaveLayout(ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if SiteType=adhstPages then begin
     LayoutNode.NodeType:=adltnPages;
@@ -5461,7 +5814,7 @@
         Site.SaveLayout(LayoutTree,ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else
     LayoutNode.NodeType:=adltnNone;
@@ -5476,6 +5829,9 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
+  fMinimization:=false;
+  FMinimizedControl:=Nil;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5490,13 +5846,13 @@
 end;
 
 destructor TAnchorDockHostSite.Destroy;
-//var i: Integer;
+var i: Integer;
 begin
-  //debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
-  {for i:=0 to ComponentCount-1 do
+  debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
+  for i:=0 to ComponentCount-1 do
     debugln(['TAnchorDockHostSite.Destroy Component ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   for i:=0 to ControlCount-1 do
-    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);}
+    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);
   FreePages;
   inherited Destroy;
 end;
@@ -5562,13 +5918,34 @@
 end;
 
 procedure TAnchorDockHeader.CloseButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
 begin
-  if Parent is TAnchorDockHostSite then begin
-    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(Parent),true);
-    TAnchorDockHostSite(Parent).CloseSite;
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
   end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(HeaderParent),true);
+    HeaderParent.CloseSite;
+  end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
+begin
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
+  end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    HeaderParent.MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5640,6 +6017,13 @@
       r.Right:=CloseButton.Left-1;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+1
+    else
+      r.Right:=MinimizeButton.Left-1;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,25 +6112,89 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
   X, Y: Integer);
+var
+  SiteMinimized:Boolean;
 begin
   inherited MouseDown(Button, Shift, X, Y);
-  if (Button=mbLeft) and DockMaster.AllowDragging then
-    DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
+  SiteMinimized:=False;
+  if Parent is TAnchorDockHostSite then
+    SiteMinimized:=(Parent as TAnchorDockHostSite).FMinimized;
+  if SiteMinimized then begin
+    DoMouseNoMoveTimer(nil);
+  end else
+    if (Button=mbLeft) and (DockMaster.AllowDragging) and (DockMaster.FOverlappingForm=nil) then
+      DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
 end;
 
+procedure  TAnchorDockHeader.MouseMove(Shift: TShiftState; X,Y: Integer);
+begin
+  inherited MouseMove(Shift, X, Y);
+  if parent<>nil then
+    if parent is TAnchorDockHostSite then
+      if (parent as TAnchorDockHostSite).FMinimized then
+        if DockMaster.FOverlappingForm=nil then
+          if FMouseTimeStartX=EmptyMouseTimeStartX then
+            StartMouseNoMoveTimer(X, Y)
+          else begin
+            if (abs(FMouseTimeStartX-X)>MouseNoMoveDelta)or(abs(FMouseTimeStartY-Y)>MouseNoMoveDelta)then
+            StopMouseNoMoveTimer;
+          end;
+end;
+
+procedure TAnchorDockHeader.MouseLeave;
+begin
+  inherited;
+  StopMouseNoMoveTimer;
+end;
+
+procedure TAnchorDockHeader.StartMouseNoMoveTimer(X, Y: Integer);
+begin
+  if DockTimer.Enabled then DockTimer.Enabled:=false;
+  DockTimer.Interval:=MouseNoMoveTime;
+  DockTimer.OnTimer:=@DoMouseNoMoveTimer;
+  DockTimer.Enabled:=true;
+end;
+
+procedure TAnchorDockHeader.StopMouseNoMoveTimer;
+begin
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  DockTimer.OnTimer:=nil;
+  DockTimer.Enabled:=false;
+end;
+
+procedure TAnchorDockHeader.DoMouseNoMoveTimer(Sender: TObject);
+begin
+  StopMouseNoMoveTimer;
+  if parent<>nil then
+    if parent is TAnchorDockHostSite then
+      if (parent as TAnchorDockHostSite).FMinimized then
+        (parent as TAnchorDockHostSite).ShowMinimizedControl;
+end;
+
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alTop;
       CloseButton.Align:=alTop;
+    end;
   end else begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alRight;
       CloseButton.Align:=alRight;
+    end;
   end;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
@@ -5787,9 +6235,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,11 +6247,22 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
   PopupMenu:=DockMaster.GetPopupMenu;
   fFocused:=false;
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
 end;
 
 { TAnchorDockCloseButton }
@@ -5844,6 +6303,44 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMinButtonNormal;
+    if not IsEnabled then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonDisabled{$ELSE}twMinButtonDisabled{$ENDIF}
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonPushed{$ELSE}twMinButtonPushed{$ENDIF}
+    else
+    if FState = bsHot then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonHot{$ELSE}twMinButtonHot{$ENDIF}
+    else
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF};
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails({$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF})) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6213,6 +6710,9 @@
   ClientRectChanged:=(WidthDiff<>0) or (HeightDiff<>0);
   if ClientRectChanged or PreferredSiteSizeAsSiteMinimum then
     AlignChilds;
+  if ClientRectChanged then
+    if DockMaster.FOverlappingForm<>nil then
+      DockMaster.HideOverlappingForm(nil);
 end;
 
 procedure TAnchorDockManager.SaveToStream(Stream: TStream);
@@ -6505,32 +7005,58 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
@@ -6560,14 +7086,47 @@
   end;
 end;
 
+function TAnchorDockSplitter.GetSpliterBoundsWithUnminimizedDockSites:TRect;
+var
+  NewLeft, NewTop: Integer;
+begin
+  if ResizeAnchor in [akLeft,akRight] then
+  begin
+    if DockParentClientSize.cx> 0 then
+    begin
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+      else
+        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+      NewTop := Top;
+    end;
+  end else
+  begin
+    if DockParentClientSize.cy> 0 then
+    begin
+      NewLeft := Left;
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewTop := Round(FPercentPosition*Parent.ClientHeight)
+      else
+        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    end;
+  end;
+  result:=Rect(NewLeft,NewTop,NewLeft+Width,NewTop+Height);
+end;
+
 procedure TAnchorDockSplitter.SaveLayout(
   LayoutNode: TAnchorDockLayoutTreeNode);
+var
+  NewLeft, NewTop: Integer;
 begin
   if ResizeAnchor in [akLeft,akRight] then
     LayoutNode.NodeType:=adltnSplitterVertical
   else
     LayoutNode.NodeType:=adltnSplitterHorizontal;
-  LayoutNode.Assign(Self);
+  LayoutNode.Assign(Self,false,false);
+  if not Enabled then begin
+    LayoutNode.BoundsRect:=GetSpliterBoundsWithUnminimizedDockSites;
+  end
 end;
 
 function TAnchorDockSplitter.HasOnlyOneSibling(Side: TAnchorKind; MinPos,
@@ -6645,7 +7204,7 @@
 begin
   inherited MouseDown(Button, Shift, X, Y);
   ATabIndex := IndexOfPageAt(X, Y);
-  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) then
+  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) and (DockMaster.FOverlappingForm=nil) then
   begin
     APage:=Page[ATabIndex];
     if (APage.ControlCount>0) and (APage.Controls[0] is TAnchorDockHostSite) then
@@ -6782,6 +7341,20 @@
   PopupMenu:=DockMaster.GetPopupMenu;
 end;
 
+{ TAnchorDockOverlappingForm }
+
+constructor TAnchorDockOverlappingForm.CreateNew(AOwner: TComponent; Num: Integer = 0);
+begin
+  inherited;
+  BorderStyle:=bsNone;
+  AnchorDockHostSite:=nil;
+end;
+
+procedure TAnchorDockOverlappingForm.MouseLeave;
+begin
+  inherited;
+end;
+
 { TAnchorDockPage }
 
 procedure TAnchorDockPage.UpdateDockCaption(Exclude: TControl);
@@ -6835,9 +7408,11 @@
 
 initialization
   DockMaster:=TAnchorDockMaster.Create(nil);
+  DockTimer:=TTimer.Create(nil);
 
 finalization
   FreeAndNil(DockMaster);
+  FreeAndNil(DockTimer);
 
 end.
 
Index: components/anchordocking/anchordockoptionsdlg.lfm
===================================================================
--- components/anchordocking/anchordockoptionsdlg.lfm	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.lfm	(working copy)
@@ -1,11 +1,13 @@
 object AnchorDockOptionsFrame: TAnchorDockOptionsFrame
   Left = 0
-  Height = 482
+  Height = 567
   Top = 0
-  Width = 416
-  ClientHeight = 482
-  ClientWidth = 416
+  Width = 490
+  ClientHeight = 567
+  ClientWidth = 490
+  DesignTimePPI = 113
   OnClick = FrameClick
+  ParentFont = False
   TabOrder = 0
   DesignLeft = 513
   DesignTop = 189
@@ -12,14 +14,15 @@
   object DragThresholdLabel: TLabel
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
-    Left = 10
-    Height = 13
-    Top = 10
-    Width = 111
-    BorderSpacing.Left = 10
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 12
+    Width = 122
+    BorderSpacing.Left = 12
+    BorderSpacing.Top = 12
     Caption = 'DragThresholdLabel'
     ParentColor = False
+    ParentFont = False
   end
   object DragThresholdTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdLabel
@@ -27,15 +30,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 23
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 31
+    Width = 466
     Max = 20
     OnChange = DragThresholdTrackBarChange
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Right = 10
+    BorderSpacing.Right = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 1
@@ -46,12 +50,13 @@
     AnchorSideTop.Control = DragThresholdLabel
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
-    Left = 127
-    Height = 23
-    Top = 5
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 141
+    Height = 27
+    Top = 8
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 20
+    ParentFont = False
     TabOrder = 0
     Visible = False
   end
@@ -59,13 +64,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = DragThresholdTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 79
-    Width = 103
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 97
+    Width = 112
+    BorderSpacing.Top = 12
     Caption = 'SplitterWidthLabel'
     ParentColor = False
+    ParentFont = False
   end
   object SplitterWidthTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdTrackBar
@@ -73,14 +79,15 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 92
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 116
+    Width = 466
     Min = 1
     OnChange = SplitterWidthTrackBarChange
     Position = 1
     Anchors = [akTop, akLeft, akRight]
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 3
@@ -89,12 +96,13 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = SplitterWidthTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 142
-    Width = 160
-    BorderSpacing.Top = 4
+    Left = 12
+    Height = 23
+    Top = 175
+    Width = 169
+    BorderSpacing.Top = 5
     Caption = 'ScaleOnResizeCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 4
@@ -103,12 +111,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 166
-    Width = 149
+    Left = 12
+    Height = 23
+    Top = 198
+    Width = 160
     Caption = 'ShowHeaderCheckBox'
     OnChange = ShowHeaderCheckBoxChange
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 5
@@ -117,12 +126,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ShowHeaderCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 190
-    Width = 191
-    BorderSpacing.Left = 15
+    Left = 30
+    Height = 23
+    Top = 221
+    Width = 208
+    BorderSpacing.Left = 18
     Caption = 'ShowHeaderCaptionCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 6
@@ -131,11 +141,12 @@
     AnchorSideLeft.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 214
-    Width = 249
+    Left = 30
+    Height = 23
+    Top = 244
+    Width = 272
     Caption = 'HideHeaderCaptionForFloatingCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 7
@@ -147,15 +158,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 122
+    Left = 136
     Height = 27
-    Top = 286
-    Width = 284
+    Top = 313
+    Width = 342
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 6
-    BorderSpacing.Right = 10
-    ItemHeight = 0
+    BorderSpacing.Left = 7
+    BorderSpacing.Right = 12
+    ItemHeight = 19
     OnDrawItem = HeaderStyleComboBoxDrawItem
+    ParentFont = False
     Style = csDropDownList
     TabOrder = 10
   end
@@ -163,23 +175,25 @@
     AnchorSideLeft.Control = ShowHeaderCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrCenter
-    Left = 20
-    Height = 13
-    Top = 293
-    Width = 96
-    BorderSpacing.Left = 10
+    Left = 24
+    Height = 19
+    Top = 317
+    Width = 105
+    BorderSpacing.Left = 12
     Caption = 'HeaderStyleLabel'
     ParentColor = False
+    ParentFont = False
   end
   object FlattenHeadersCheckBox: TCheckBox
     AnchorSideLeft.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 238
-    Width = 164
+    Left = 30
+    Height = 23
+    Top = 267
+    Width = 175
     Caption = 'FlattenHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 8
@@ -188,11 +202,12 @@
     AnchorSideLeft.Control = FlattenHeadersCheckBox
     AnchorSideTop.Control = FlattenHeadersCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 262
-    Width = 154
+    Left = 30
+    Height = 23
+    Top = 290
+    Width = 164
     Caption = 'FilledHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 9
@@ -201,11 +216,12 @@
     AnchorSideLeft.Control = FilledHeadersCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 313
-    Width = 175
+    Left = 30
+    Height = 23
+    Top = 340
+    Width = 189
     Caption = 'HighlightFocusedCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 11
@@ -215,13 +231,14 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = SplitterWidthLabel
     AnchorSideTop.Side = asrCenter
-    Left = 119
-    Height = 23
-    Top = 74
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 131
+    Height = 27
+    Top = 93
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 10
     MinValue = 1
+    ParentFont = False
     TabOrder = 2
     Value = 1
     Visible = False
@@ -228,15 +245,16 @@
   end
   object HeaderAlignTopLabel: TLabel
     AnchorSideLeft.Control = DragThresholdLabel
-    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Control = DockSitesCanBeMinimized
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 347
-    Width = 117
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 398
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignTopLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignTopTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -244,10 +262,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 360
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 417
+    Width = 466
     Frequency = 10
     Max = 150
     OnChange = HeaderAlignTopTrackBarChange
@@ -254,7 +272,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 13
@@ -264,12 +283,13 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignTopLabel
     AnchorSideTop.Side = asrCenter
-    Left = 133
-    Height = 23
-    Top = 342
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 394
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 150
+    ParentFont = False
     TabOrder = 12
     Visible = False
   end
@@ -277,13 +297,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = HeaderAlignTopTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 417
-    Width = 120
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 484
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignLeftLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignLeftTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -291,10 +312,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 430
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 503
+    Width = 466
     Frequency = 10
     Max = 200
     OnChange = HeaderAlignLeftTrackBarChange
@@ -301,7 +322,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 15
@@ -311,13 +333,28 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignLeftLabel
     AnchorSideTop.Side = asrCenter
-    Left = 136
-    Height = 23
-    Top = 412
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 480
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 200
+    ParentFont = False
     TabOrder = 14
     Visible = False
   end
+  object DockSitesCanBeMinimized: TCheckBox
+    AnchorSideLeft.Control = FilledHeadersCheckBox
+    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Side = asrBottom
+    Left = 30
+    Height = 23
+    Top = 363
+    Width = 185
+    Caption = 'DockSitesCanBeMinimized'
+    ParentFont = False
+    ParentShowHint = False
+    ShowHint = True
+    TabOrder = 16
+  end
 end
Index: components/anchordocking/anchordockoptionsdlg.pas
===================================================================
--- components/anchordocking/anchordockoptionsdlg.pas	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.pas	(working copy)
@@ -37,6 +37,7 @@
     HeaderStyleLabel: TLabel;
     HideHeaderCaptionForFloatingCheckBox: TCheckBox;
     HighlightFocusedCheckBox: TCheckBox;
+    DockSitesCanBeMinimized: TCheckBox;
     ScaleOnResizeCheckBox: TCheckBox;
     ShowHeaderCaptionCheckBox: TCheckBox;
     ShowHeaderCheckBox: TCheckBox;
@@ -299,6 +300,7 @@
   HeaderStyleLabel.Enabled:=HasHeaders;
   HeaderStyleComboBox.Enabled:=HasHeaders;
   HighlightFocusedCheckBox.Enabled:=HasHeaders;
+  DockSitesCanBeMinimized.Enabled:=HasHeaders;
 end;
 
 constructor TAnchorDockOptionsFrame.Create(TheOwner: TComponent);
@@ -356,6 +358,7 @@
   TheSettings.HeaderFilled:=FilledHeadersCheckBox.Checked;
   TheSettings.HeaderStyle:=TADHeaderStyle(HeaderStyleComboBox.ItemIndex);
   TheSettings.HeaderHighlightFocused:=HighlightFocusedCheckBox.Checked;
+  TheSettings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized.Checked;
 end;
 
 procedure TAnchorDockOptionsFrame.LoadFromSettings(
@@ -429,6 +432,10 @@
   HighlightFocusedCheckBox.Checked:=TheSettings.HeaderHighlightFocused;
   HighlightFocusedCheckBox.Caption:=adrsHighlightFocused;
   HighlightFocusedCheckBox.Hint:=adrsHighlightFocusedHint;
+
+  DockSitesCanBeMinimized.Checked:=TheSettings.DockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Caption:=adrsDockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Hint:=adrsDockSitesCanBeMinimizedHint;
 end;
 
 end.
Index: components/anchordocking/anchordockpanel.pas
===================================================================
--- components/anchordocking/anchordockpanel.pas	(revision 59428)
+++ components/anchordocking/anchordockpanel.pas	(working copy)
@@ -55,7 +55,7 @@
   begin
 
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,false);
     LayoutNode.Name:={OneControl.}Name;
 
     TAnchorDockHostSite(OneControl).SaveLayout(LayoutTree,LayoutNode);
Index: components/anchordocking/anchordockstorage.pas
===================================================================
--- components/anchordocking/anchordockstorage.pas	(revision 59428)
+++ components/anchordocking/anchordockstorage.pas	(working copy)
@@ -64,6 +64,7 @@
     FTabPosition: TTabPosition;
     FWindowState: TWindowState;
     FControlLocation: TADLControlLocation;
+    FMinimized: Boolean;
     function GetAnchors(Site: TAnchorKind): string;
     function GetBottom: integer;
     function GetHeight: integer;
@@ -90,6 +91,7 @@
     procedure SetTop(const AValue: integer);
     procedure SetWidth(const AValue: integer);
     procedure SetWindowState(const AValue: TWindowState);
+    procedure SetMinimized(const AValue: boolean);
   public
     constructor Create;
     destructor Destroy; override;
@@ -96,7 +98,7 @@
     procedure Clear;
     function IsEqual(Node: TAnchorDockLayoutTreeNode): boolean;
     procedure Assign(Node: TAnchorDockLayoutTreeNode); overload;
-    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean=false); overload;
+    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean); overload;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
     procedure LoadFromConfig(Path: string; Config: TRttiXMLConfig); overload;
     procedure SaveToConfig(Config: TConfigStorage); overload;
@@ -106,7 +108,7 @@
     procedure CheckConsistency; virtual;
 
     // simplifying
-    procedure Simplify(ExistingNames: TStrings);
+    procedure Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
     procedure DeleteNode(ChildNode: TAnchorDockLayoutTreeNode);
     function FindNodeBoundSplitter(ChildNode: TAnchorDockLayoutTreeNode;
                                    Side: TAnchorKind): TAnchorDockLayoutTreeNode;
@@ -135,6 +137,7 @@
     property Monitor: integer read FMonitor write SetMonitor;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property TabPosition: TTabPosition read FTabPosition write SetTabPosition;
+    property Minimized: Boolean read FMinimized write SetMinimized;
     function Count: integer;
     function IsSplitter: boolean;
     function IsRootWindow: boolean;
@@ -988,6 +991,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockLayoutTreeNode.SetMinimized(const AValue: boolean);
+begin
+  if FMinimized=AValue then exit;
+  FMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockLayoutTreeNode.SetTop(const AValue: integer);
 begin
   if Top=AValue then exit;
@@ -1084,6 +1094,7 @@
   BoundSplitterPos:=Node.BoundSplitterPos;
   WorkAreaRect:=Node.WorkAreaRect;
   Monitor:=Node.Monitor;
+  Minimized:=Node.Minimized;
   for a:=low(TAnchorKind) to high(TAnchorKind) do
     Anchors[a]:=Node.Anchors[a];
   while Count>Node.Count do Nodes[Count-1].Free;
@@ -1098,9 +1109,10 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean=false);
+procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean);
 var
   AnchorControl: TControl;
+  ParentForm:TCustomForm;
   a: TAnchorKind;
 begin
   Name:=AControl.Name;
@@ -1109,12 +1121,18 @@
   else
     BoundsRect:=AControl.BoundsRect;
   Align:=AControl.Align;
+  Minimized:=AMinimized;
   if (AControl.Parent=nil) and (AControl is TCustomForm) then begin
     WindowState:=TCustomForm(AControl).WindowState;
     Monitor:=TCustomForm(AControl).Monitor.MonitorNum;
     WorkAreaRect:=TCustomForm(AControl).Monitor.WorkareaRect;
-  end else
-    WindowState:=GetParentForm(AControl).WindowState;
+  end else begin
+    ParentForm:=GetParentForm(AControl);
+    if assigned(ParentForm) then
+      WindowState:=ParentForm.WindowState
+    else
+      WindowState:=wsNormal;
+  end;
   if AControl is TCustomTabControl then
     TabPosition:=TCustomTabControl(AControl).TabPosition
   else
@@ -1137,6 +1155,7 @@
   Clear;
   Name:=Config.GetValue('Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue('Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue('Minimized',false);
   Left:=Config.GetValue('Bounds/Left',0);
   Top:=Config.GetValue('Bounds/Top',0);
   Width:=Config.GetValue('Bounds/Width',0);
@@ -1171,6 +1190,7 @@
   Clear;
   Name:=Config.GetValue(Path+'Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue(Path+'Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue(Path+'Minimized',false);
   Left:=Config.GetValue(Path+'Bounds/Left',0);
   Top:=Config.GetValue(Path+'Bounds/Top',0);
   Width:=Config.GetValue(Path+'Bounds/Width',0);
@@ -1219,6 +1239,7 @@
                                           ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue('Header/TabPosition',ADLTabPostionNames[TabPosition],
                                              ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue('Minimized',Minimized,False);
   Config.SetDeleteValue('Monitor',Monitor,0);
   Config.SetDeleteValue('ChildCount',Count,0);
   for i:=1 to Count do begin
@@ -1252,6 +1273,7 @@
                                                ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue(Path+'Header/TabPosition',ADLTabPostionNames[TabPosition],
                                                   ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue(Path+'Minimized',Minimized,False);
   Config.SetDeleteValue(Path+'Monitor',Monitor,0);
   Config.SetDeleteValue(Path+'ChildCount',Count,0);
   for i:=1 to Count do
@@ -1397,7 +1419,7 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings);
+procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
 { Simplification rules:
    1. Control nodes without existing name are deleted.
    2. Empty layouts and pages are deleted
@@ -1406,16 +1428,18 @@
 var
   i: Integer;
   ChildNode: TAnchorDockLayoutTreeNode;
+  NodeMinimized:boolean;
 begin
   // simplify children
   i:=Count-1;
   while i>=0 do begin
     ChildNode:=Nodes[i];
-    ChildNode.Simplify(ExistingNames);
+    NodeMinimized:=ParentMinimized or ChildNode.Minimized;
+    ChildNode.Simplify(ExistingNames,NodeMinimized);
 
     if (ChildNode.NodeType=adltnControl) then begin
       // leaf node => check if there is a control
-      if (ChildNode.Name='') or (ExistingNames.IndexOf(ChildNode.Name)<0) then
+      if (ChildNode.Name='') or ((ExistingNames.IndexOf(ChildNode.Name)<0) and (not NodeMinimized)) then
         DeleteNode(ChildNode);
     end else if ChildNode.IsSplitter then begin
       // splitter
@@ -1424,7 +1448,7 @@
         ChildNode[0].Free;
     end else if ChildNode.NodeType=adltnCustomSite then begin
       // custom dock site
-    end else if ChildNode.Count=0 then begin
+    end else if (ChildNode.Count=0)and(not NodeMinimized) then begin
       // inner node without child => delete
       DeleteNode(ChildNode);
     end else if (ChildNode.Count=1)
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59428)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';
@@ -82,6 +83,8 @@
   adrsFilledHeadersHint = 'Fill headers of docked controls';
   adrsHighlightFocused = 'Highlight focused';
   adrsHighlightFocusedHint = 'Highlight header of focused docked control';
+  adrsDockSitesCanBeMinimized = 'Dock sites can be minimized';
+  adrsDockSitesCanBeMinimizedHint = 'Dock sites can be minimized';
 
 implementation
 
Index: components/anchordocking/design/anchordesktopoptions.pas
===================================================================
--- components/anchordocking/design/anchordesktopoptions.pas	(revision 59428)
+++ components/anchordocking/design/anchordesktopoptions.pas	(working copy)
@@ -272,7 +272,7 @@
         // custom dock site
         LayoutNode:=FTree.NewNode(FTree.Root);
         LayoutNode.NodeType:=adltnCustomSite;
-        LayoutNode.Assign(AForm);
+        LayoutNode.Assign(AForm,false,false);
         // can have one normal dock site
         Site:=TAnchorDockManager(AForm.DockManager).GetChildSite;
         if Site<>nil then begin
@@ -287,7 +287,7 @@
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    FTree.Root.Simplify(VisibleControls);
+    FTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59428)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -109,6 +109,11 @@
 const ADAutoSizingReason = 'TAnchorDockMaster Delayed';
 {$ENDIF}
 
+const EmptyMouseTimeStartX=low(Integer);
+      MouseNoMoveDelta=5;
+      MouseNoMoveTime=500;
+      HideOverlappingFormByMouseLoseTime=500;
+
 type
   TAnchorDockHostSite = class;
 
@@ -123,6 +128,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +146,13 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
+    fUseTimer:Boolean;
+    FMouseTimeStartX,FMouseTimeStartY:Integer;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -147,6 +164,11 @@
           PreferredHeight: integer; WithThemeSpace: Boolean); override;
     procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X,
              Y: Integer); override;
+    procedure MouseMove(Shift: TShiftState; X,Y: Integer); override;
+    procedure MouseLeave;  override;
+    procedure StartMouseNoMoveTimer(X, Y: Integer);
+    procedure StopMouseNoMoveTimer;
+    procedure DoMouseNoMoveTimer(Sender: TObject);
     procedure UpdateHeaderControls;
     procedure SetAlign(Value: TAlign); override;
     procedure DoOnShowHint(HintInfo: PHintInfo); override;
@@ -154,6 +176,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -190,6 +213,7 @@
     procedure SetBoundsKeepDockBounds(ALeft, ATop, AWidth, AHeight: integer); // movement for scaling keeps the DockBounds
     function SideAnchoredControlCount(Side: TAnchorKind): integer;
     function HasAnchoredControls: boolean;
+    function GetSpliterBoundsWithUnminimizedDockSites:TRect;
     procedure SaveLayout(LayoutNode: TAnchorDockLayoutTreeNode);
     function HasOnlyOneSibling(Side: TAnchorKind; MinPos, MaxPos: integer): TControl;
     property DockRestoreBounds: TRect read FDockRestoreBounds write FDockRestoreBounds;
@@ -241,6 +265,14 @@
   end;
   TAnchorDockPageControlClass = class of TAnchorDockPageControl;
 
+
+  TAnchorDockOverlappingForm = class(TCustomForm)
+  public
+    AnchorDockHostSite:TAnchorDockHostSite;
+    Panel:TPanel;
+    constructor CreateNew(AOwner: TComponent; Num: Integer = 0); override;
+  end;
+
   { TAnchorDockHostSite
     This form is the dockhostsite for all controls.
     When docked together they build a tree structure with the docked controls
@@ -262,7 +294,10 @@
     FPages: TAnchorDockPageControl;
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
-    fUpdateLayout: integer;
+    fUpdateLayout: Integer;
+    FMinimized: Boolean;
+    fMinimization: Boolean;
+    FMinimizedControl: TControl;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +354,10 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
+    procedure AsyncMinimizeSite(Data: PtrInt);
+    procedure ShowMinimizedControl;
+    procedure HideMinimizedControl;
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -329,6 +368,7 @@
     procedure UpdateDockCaption(Exclude: TControl = nil); override;
     procedure UpdateHeaderAlign;
     procedure UpdateHeaderShowing;
+    function CanBeMinimized(out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
     procedure BeginUpdateLayout;
     procedure EndUpdateLayout;
     function UpdatingLayout: boolean;
@@ -431,6 +471,7 @@
     FShowHeader: boolean;
     FShowHeaderCaption: boolean;
     FSplitterWidth: integer;
+    FDockSitecCanBeMinimized: boolean;
     procedure SetAllowDragging(AValue: boolean);
     procedure SetDockOutsideMargin(AValue: integer);
     procedure SetDockParentMargin(AValue: integer);
@@ -448,6 +489,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitecCanBeMinimized(AValue: boolean);
   public
     property DragTreshold: integer read FDragTreshold write SetDragTreshold;
     property DockOutsideMargin: integer read FDockOutsideMargin write SetDockOutsideMargin;
@@ -466,6 +508,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused;
+    property DockSitesCanBeMinimized: boolean read FDockSitecCanBeMinimized write SetDockSitecCanBeMinimized;
     procedure IncreaseChangeStamp; inline;
     property ChangeStamp: integer read FChangeStamp;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
@@ -502,6 +545,7 @@
     FHeaderFlatten: boolean;
     FHeaderFilled: boolean;
     FHeaderHighlightFocused: boolean;
+    FDockSitesCanBeMinimized: boolean;
     FIdleConnected: Boolean;
     FManagerClass: TAnchorDockManagerClass;
     FOnCreateControl: TADCreateControlEvent;
@@ -531,6 +575,7 @@
     fPopupMenu: TPopupMenu;
     // Used by RestoreLayout:
     WorkArea, SrcWorkArea: TRect;
+    FOverlappingForm:TAnchorDockOverlappingForm;
 
     function GetControls(Index: integer): TControl;
     function GetLocalizedHeaderHint: string;
@@ -541,6 +586,9 @@
     function GetNodeSite(Node: TAnchorDockLayoutTreeNode): TAnchorDockHostSite;
     procedure MapTreeToControls(Tree: TAnchorDockLayoutTree);
     function RestoreLayout(Tree: TAnchorDockLayoutTree; Scale: boolean): boolean;
+    procedure SetMinimizedState(Tree: TAnchorDockLayoutTree);
+    procedure UpdateHeaders;
+    procedure SetnodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
     procedure EnableAllAutoSizing;
     procedure ClearLayoutProperties(AControl: TControl; NewAlign: TAlign = alClient);
     procedure PopupMenuPopup(Sender: TObject);
@@ -561,6 +609,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitesCanBeMinimized(AValue: boolean);
 
     procedure SetShowMenuItemShowHeader(AValue: boolean);
     procedure SetupSite(Site: TWinControl; ANode: TAnchorDockLayoutTreeNode;
@@ -584,8 +633,12 @@
     procedure SetHideHeaderCaptionFloatingControl(const AValue: boolean);
     procedure SetSplitterWidth(const AValue: integer);
     procedure OnIdle(Sender: TObject; var Done: Boolean);
+    procedure StartHideOverlappingTimer;
+    procedure StopHideOverlappingTimer;
     procedure AsyncSimplify({%H-}Data: PtrInt);
   public
+    procedure ShowOverlappingForm;
+    procedure HideOverlappingForm(Sender: TObject);
     constructor Create(AOwner: TComponent); override;
     destructor Destroy; override;
     function FullRestoreLayout(Tree: TAnchorDockLayoutTree; Scale: Boolean): Boolean;
@@ -680,6 +733,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten default true;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled default true;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused default false;
+    property DockSitesCanBeMinimized: boolean read FDockSitesCanBeMinimized write SetDockSitesCanBeMinimized default false;
 
     property SplitterWidth: integer read FSplitterWidth write SetSplitterWidth default 4;
     property ScaleOnResize: boolean read FScaleOnResize write SetScaleOnResize default true; // scale children when resizing a site
@@ -698,6 +752,7 @@
 
 var
   DockMaster: TAnchorDockMaster = nil;
+  DockTimer: TTimer = nil;
 
 const
   ADHeaderStyleNames: array[TADHeaderStyle] of string = (
@@ -970,6 +1025,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -1361,6 +1437,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockSettings.SetDockSitecCanBeMinimized(AValue: boolean);
+begin
+  if FDockSitecCanBeMinimized=AValue then Exit;
+  FDockSitecCanBeMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockSettings.Assign(Source: TAnchorDockSettings);
 begin
   FAllowDragging := Source.FAllowDragging;
@@ -1381,6 +1464,7 @@
   FShowHeaderCaption := Source.FShowHeaderCaption;
   FSplitterWidth := Source.FSplitterWidth;
   FHeaderHighlightFocused:=Source.FHeaderHighlightFocused;
+  FDockSitecCanBeMinimized:=Source.FDockSitecCanBeMinimized;
 end;
 
 procedure TAnchorDockSettings.IncreaseChangeStamp;
@@ -1407,6 +1491,7 @@
   HeaderFlatten:=Config.GetValue('HeaderFlatten',true);
   HeaderFilled:=Config.GetValue('HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue('HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue('DockSitecCanBeMinimized',False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1429,6 +1514,7 @@
   Config.SetDeleteValue(Path+'HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue(Path+'HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue(Path+'HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue(Path+'DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
 end;
 
 procedure TAnchorDockSettings.SaveToConfig(Config: TConfigStorage);
@@ -1450,6 +1536,7 @@
   Config.SetDeleteValue('HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue('HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue('HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue('DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1472,6 +1559,7 @@
       and (HeaderFlatten=Settings.HeaderFlatten)
       and (HeaderFilled=Settings.HeaderFilled)
       and (HeaderHighlightFocused=Settings.HeaderHighlightFocused)
+      and (DockSitesCanBeMinimized=Settings.DockSitesCanBeMinimized)
       ;
 end;
 
@@ -1494,6 +1582,7 @@
   HeaderFlatten:=Config.GetValue(Path+'HeaderFlatten',true);
   HeaderFilled:=Config.GetValue(Path+'HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue(Path+'HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue(Path+'DockSitecCanBeMinimized',False);
 end;
 
 { TAnchorDockMaster }
@@ -2021,6 +2110,8 @@
     aHostSite:=TAnchorDockHostSite(Site);
     aHostSite.Header.HeaderPosition:=ANode.HeaderPosition;
     aHostSite.DockRestoreBounds:=NewBounds;
+    //aHostSite.FMinimized:=ANode.Minimized;
+    //we update aHostSite.FMinimized in TAnchorDockMaster.SetMinimizedState
     if (ANode.NodeType<>adltnPages) and (aHostSite.Pages<>nil) then
       aHostSite.FreePages;
   end;
@@ -2040,6 +2131,25 @@
   fTreeNameToDocker[Node.Name]:=Result;
 end;
 
+procedure TAnchorDockMaster.SetNodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
+var
+  HostSite:TAnchorDockHostSite;
+  i:integer;
+begin
+  HostSite:=GetNodeSite(ANode);
+  if Assigned(HostSite) then
+    if HostSite.FMinimized<>ANode.Minimized then
+      Application.QueueAsyncCall(@HostSite.AsyncMinimizeSite,0);
+      //HostSite.MinimizeSite;
+  for i:=0 to ANode.Count-1 do
+    SetnodeMinimizedState(ANode.Nodes[i]);
+end;
+
+procedure TAnchorDockMaster.SetMinimizedState(Tree: TAnchorDockLayoutTree);
+begin
+  SetnodeMinimizedState(Tree.Root);
+end;
+
 function TAnchorDockMaster.RestoreLayout(Tree: TAnchorDockLayoutTree;
   Scale: boolean): boolean;
 
@@ -2193,7 +2303,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -2358,7 +2468,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -2368,6 +2478,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -2422,11 +2533,54 @@
   OptionsChanged;
 end;
 
+procedure TAnchorDockMaster.StartHideOverlappingTimer;
+begin
+  if not DockTimer.Enabled then begin
+    DockTimer.Interval:=HideOverlappingFormByMouseLoseTime;
+    DockTimer.OnTimer:=@HideOverlappingForm;
+    DockTimer.Enabled:=true;
+  end;
+end;
+
+procedure TAnchorDockMaster.StopHideOverlappingTimer;
+begin
+  DockTimer.Enabled:=False;
+  DockTimer.Interval:=0;
+  DockTimer.OnTimer:=nil;
+end;
+
+function IsParentControl(aParent, aControl: TControl): boolean;
+begin
+  while (aControl <> nil) and (aControl.Parent <> nil) do
+  begin
+    if (aControl=aParent) then
+      exit(true);
+    aControl := aControl.Parent;
+  end;
+  result:=aControl=aParent;
+end;
+
+
 procedure TAnchorDockMaster.OnIdle(Sender: TObject; var Done: Boolean);
+var
+  MousePos: TPoint;
+  Bounds:Trect;
 begin
   if Done then ;
-  IdleConnected:=false;
   Restoring:=false;
+  if FOverlappingForm=nil then
+    IdleConnected:=false
+  else begin
+    GetCursorPos(MousePos);
+    Bounds.TopLeft:=FOverlappingForm.ClientToScreen(point(0,0));
+    Bounds.BottomRight:=FOverlappingForm.ClientToScreen(point(FOverlappingForm.Width,FOverlappingForm.Height));
+    if not IsParentControl(FOverlappingForm, GetCaptureControl) then begin
+      if not PtInRect(Bounds,MousePos) then
+          StartHideOverlappingTimer
+        else
+          StopHideOverlappingTimer;
+    end;
+  end;
 end;
 
 procedure TAnchorDockMaster.AsyncSimplify(Data: PtrInt);
@@ -2514,6 +2668,24 @@
   InvalidateHeaders;
 end;
 
+procedure TAnchorDockMaster.SetDockSitesCanBeMinimized(AValue: boolean);
+var
+  i:integer;
+  Site: TAnchorDockHostSite;
+begin
+  if FDockSitesCanBeMinimized=AValue then Exit;
+  FDockSitesCanBeMinimized:=AValue;
+  for i:=0 to ComponentCount-1 do begin
+    Site:=TAnchorDockHostSite(Components[i]);
+    if not (Site is TAnchorDockHostSite) then continue;
+    if (Site.Header<>nil) then begin
+      DisableControlAutoSizing(Site);
+      Site.UpdateHeaderShowing;
+    end;
+  end;
+  EnableAllAutoSizing;
+  OptionsChanged;
+end;
 procedure TAnchorDockMaster.SetScaleOnResize(AValue: boolean);
 begin
   if FScaleOnResize=AValue then Exit;
@@ -2598,6 +2770,9 @@
     if (Site.Header<>nil) then begin
       DisableControlAutoSizing(Site);
       Site.UpdateHeaderShowing;
+      if Site.fminimized then
+        if not AValue then
+          site.MinimizeSite;
     end;
   end;
   EnableAllAutoSizing;
@@ -2668,6 +2843,20 @@
     EnableAllAutoSizing;
 end;
 
+procedure TAnchorDockMaster.ShowOverlappingForm;
+begin
+  FOverlappingForm.Show;
+  IdleConnected:=true;
+end;
+
+procedure TAnchorDockMaster.HideOverlappingForm(Sender: TObject);
+begin
+  StopHideOverlappingTimer;
+  FOverlappingForm.Hide;
+  FOverlappingForm.AnchorDockHostSite.HideMinimizedControl;
+  IdleConnected:=false;
+end;
+
 constructor TAnchorDockMaster.Create(AOwner: TComponent);
 begin
   inherited Create(AOwner);
@@ -2698,14 +2887,14 @@
   FPageClass:=TAnchorDockPage;
   FRestoreLayouts:=TAnchorDockRestoreLayouts.Create;
   FHeaderHighlightFocused:=false;
+  FDockSitesCanBeMinimized:=false;
+  FOverlappingForm:=nil;
 end;
 
 destructor TAnchorDockMaster.Destroy;
 var
   AControl: TControl;
-  {$IFDEF VerboseAnchorDocking}
-  i: Integer;
-  {$ENDIF}
+  i, j: Integer;
 begin
   QueueSimplify:=false;
   FreeAndNil(FRestoreLayouts);
@@ -2727,6 +2916,12 @@
     debugln(['TAnchorDockMaster.Destroy ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   end;
   {$ENDIF}
+  for i:=0 to ComponentCount-1 do begin
+    for j:=0 to ComponentCount-1 do begin
+      if i<>j then
+        TControl(Components[i]).RemoveAllHandlersOfObject(TControl(Components[j]));
+  end;
+  end;
   inherited Destroy;
 end;
 
@@ -3018,7 +3213,8 @@
   i:=Screen.CustomFormCount-1;
   while i>=0 do begin
     AForm:=GetParentForm(Screen.CustomForms[i]);
-    AForm.Hide;
+    if Assigned(AForm)then
+      AForm.Hide;
     i:=Min(i,Screen.CustomFormCount)-1;
   end;
 
@@ -3062,8 +3258,11 @@
   end;
 end;
 
-function GetParentFormOrDockPanel(Control: TControl): TCustomForm;
+function GetParentFormOrDockPanel(Control: TControl; TopForm:Boolean=true): TCustomForm;
+var
+  oldControl: TControl;
 begin
+  oldControl:=Control;
   while (Control <> nil) and (Control.Parent <> nil) do
   begin
     if (Control is TAnchorDockPanel) then
@@ -3076,6 +3275,18 @@
     Result := TCustomForm(Control)
   else
     Result := nil;
+  if not TopForm then begin
+    if Control is TAnchorDockPanel then
+      exit;
+    Control:=oldControl;
+    while (Control <> nil) and (Control.Parent <> nil) do
+    begin
+      Control := Control.Parent;
+      if (Control is TCustomForm) then
+        Break;
+    end;
+    Result := TCustomForm(Control);
+  end;
 end;
 
 procedure TAnchorDockMaster.SaveMainLayoutToTree(LayoutTree: TAnchorDockLayoutTree);
@@ -3088,12 +3299,12 @@
   AFormOrDockPanel: TWinControl;
   VisibleControls: TStringList;
 
-  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean);
+  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean; AMinimized:boolean);
   begin
     // custom dock site
     LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
     LayoutNode.NodeType:=adltnCustomSite;
-    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel);
+    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel,AMinimized);
     // can have one normal dock site
     if SaveChildren then
     begin
@@ -3124,7 +3335,7 @@
       debugln(['TAnchorDockMaster.SaveMainLayoutToTree AForm=',DbgSName(AFormOrDockPanel)]);
       DebugWriteChildAnchors(AFormOrDockPanel,true,true);
       if AFormOrDockPanel is TAnchorDockPanel then begin
-        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),{false}true);
+        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),true,false);
         //LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         //TAnchorDockPanel(AFormOrDockPanel).SaveLayout(LayoutTree,LayoutNode);
       end else if AFormOrDockPanel is TAnchorDockHostSite then begin
@@ -3132,12 +3343,12 @@
         LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         Site.SaveLayout(LayoutTree,LayoutNode);
       end else if IsCustomSite(AFormOrDockPanel) then begin
-        SaveFormOrDockPanel(AFormOrDockPanel,true);
+        SaveFormOrDockPanel(AFormOrDockPanel,true,false);
       end else
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    LayoutTree.Root.Simplify(VisibleControls);
+    LayoutTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;
@@ -3157,7 +3368,7 @@
     (AControl as TAnchorDockPanel).SaveLayout(LayoutTree,LayoutTree.Root);
   end else if IsCustomSite(AControl) then begin
     LayoutTree.Root.NodeType:=adltnCustomSite;
-    LayoutTree.Root.Assign(AControl);
+    LayoutTree.Root.Assign(AControl,false,false);
     // can have one normal dock site
     Site:=TAnchorDockManager(AControl.DockManager).GetChildSite;
     if Site<>nil then begin
@@ -3252,7 +3463,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -3262,6 +3473,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -3323,6 +3535,7 @@
   HeaderFlatten                    := Settings.HeaderFlatten;
   HeaderFilled                     := Settings.HeaderFilled;
   HeaderHighlightFocused           := Settings.HeaderHighlightFocused;
+  DockSitesCanBeMinimized          := Settings.DockSitesCanBeMinimized;
 end;
 
 procedure TAnchorDockMaster.SaveSettings(Settings: TAnchorDockSettings);
@@ -3343,6 +3556,7 @@
   Settings.HeaderFlatten:=HeaderFlatten;
   Settings.HeaderFilled:=HeaderFilled;
   Settings.HeaderHighlightFocused:=HeaderHighlightFocused;
+  Settings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized;
 end;
 
 function TAnchorDockMaster.SettingsAreEqual(Settings: TAnchorDockSettings
@@ -3664,6 +3878,24 @@
   LUIncreaseChangeStamp64(FOptionsChangeStamp);
 end;
 
+procedure TAnchorDockMaster.UpdateHeaders;
+var
+  i: Integer;
+  AControl: TControl;
+  AHostSite: TAnchorDockHostSite;
+begin
+    for i:=0 to ControlCount-1 do begin
+      AControl:=Controls[i];
+      if not DockedControlIsVisible(AControl) then continue;
+      while Assigned(AControl) do
+      begin
+        if AControl is TAnchorDockHostSite then
+          TAnchorDockHostSite(AControl).UpdateHeaderShowing;
+        AControl:=AControl.parent;
+      end;
+    end;
+end;
+
 { TAnchorDockHostSite }
 
 procedure TAnchorDockHostSite.SetHeaderSide(const AValue: TAnchorKind);
@@ -3680,6 +3912,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -4119,6 +4352,8 @@
 end;
 
 procedure TAnchorDockHostSite.FreePages;
+var
+  i:Integer;
 begin
   FreeAndNil(FPages);
 end;
@@ -4233,6 +4468,14 @@
         akRight: NewBounds.Right:=AControl.Left+AControl.Width;
         akBottom: NewBounds.Bottom:=AControl.Top+AControl.Height;
         end;
+        if (sibling is TAnchorDockHostSite) then
+        if (sibling as TAnchorDockHostSite).FMinimized then begin
+          (sibling as TAnchorDockHostSite).FMinimized:=false;
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Parent:=(sibling as TAnchorDockHostSite);
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Visible:=True;
+          (sibling as TAnchorDockHostSite).FMinimizedControl:=nil;
+          (sibling as TAnchorDockHostSite).UpdateHeaderAlign;
+        end;
         Sibling.BoundsRect:=NewBounds;
       end;
     end;
@@ -4306,6 +4549,13 @@
       FSiteType:=adhstOneControl;
       OnlySiteLeft.Align:=alClient;
       Header.Parent:=Self;
+      if OnlySiteLeft.FMinimized then begin
+        OnlySiteLeft.FMinimized:=false;
+        OnlySiteLeft.FMinimizedControl.Parent:=OnlySiteLeft;
+        OnlySiteLeft.FMinimizedControl.Visible:=True;
+        OnlySiteLeft.FMinimizedControl:=nil;
+        UpdateHeaderAlign;
+      end;
       UpdateHeaderAlign;
 
       //debugln(['TAnchorDockHostSite.RemoveControlFromLayout.ConvertToOneControlType AFTER CONVERT "',Caption,'" to onecontrol OnlySiteLeft="',OnlySiteLeft.Caption,'"']);
@@ -4465,7 +4715,7 @@
     debugln(['TAnchorDockHostSite.Simplify ',DbgSName(Self),' ',DbgSName(AControl)]);
     if AControl is TAnchorDockHostSite then
       SimplifyOneControl
-    else if (AControl=nil) or (csDestroying in AControl.ComponentState) then
+    else if ((AControl=nil) or (csDestroying in AControl.ComponentState)) then
       DockMaster.NeedFree(Self);
   end;
 end;
@@ -4577,7 +4827,8 @@
     Result:=Controls[i];
     if Result.Owner<>Self then exit;
   end;
-  Result:=nil;
+  result:=FMinimizedControl;
+  //Result:=nil;
 end;
 
 function TAnchorDockHostSite.GetSiteCount: integer;
@@ -5165,6 +5416,117 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+function TAnchorDockHostSite.CanBeMinimized(out Splitter: TAnchorDockSplitter;
+                                            out SplitterAnchorKind:TAnchorKind):boolean;
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+begin
+  result:=false;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) then
+      result:=true;
+  end
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+begin
+  //Application.QueueAsyncCall(@AsyncMinimizeSite,0);
+  AsyncMinimizeSite(0);
+end;
+
+procedure TAnchorDockHostSite.AsyncMinimizeSite(Data: PtrInt);
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  fMinimization:=true;
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  if FMinimized then
+    AControl:=FMinimizedControl
+  else
+    AControl:=GetOneControl;
+  if CanBeMinimized(Splitter,SplitterAnchorKind) or FMinimized then begin
+    FMinimized:=not FMinimized;
+    if FMinimized then begin
+      FMinimizedControl:=AControl;
+      AControl.Visible:=False;
+      AControl.Parent:=nil;
+    end else begin
+      AControl.Parent:=self;
+      AControl.Visible:=True;
+      FMinimizedControl:=nil;
+    end;
+    Splitter.Enabled:=AControl.Visible;
+    UpdateHeaderAlign;
+    dockmaster.UpdateHeaders;
+    Splitter.SetBoundsPercentually;
+  end;
+  fMinimization:=false;
+end;
+
+procedure TAnchorDockHostSite.ShowMinimizedControl;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  SpliterRect,OverlappingFormRect:TRect;
+begin
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    SpliterRect:=Splitter.GetSpliterBoundsWithUnminimizedDockSites;
+    OverlappingFormRect:=BoundsRect;
+    case SplitterAnchorKind of
+         akTop:OverlappingFormRect.Top:=SpliterRect.Bottom;
+        akLeft:OverlappingFormRect.Left:=SpliterRect.Right;
+       akRight:OverlappingFormRect.Right:=SpliterRect.Left;
+      akBottom:OverlappingFormRect.Bottom:=SpliterRect.Top;
+    end;
+    DockMaster.FOverlappingForm:=TAnchorDockOverlappingForm.CreateNew(self);
+    DockMaster.FOverlappingForm.BoundsRect:=OverlappingFormRect;
+    DockMaster.FOverlappingForm.Parent:=GetParentFormOrDockPanel(self,false);
+    DockMaster.FOverlappingForm.AnchorDockHostSite:=self;
+    header.Parent:=DockMaster.FOverlappingForm;
+    FMinimizedControl.Parent:=DockMaster.FOverlappingForm.Panel;
+    FMinimizedControl.Show;
+    DockMaster.ShowOverlappingForm;
+  end;
+end;
+
+procedure TAnchorDockHostSite.HideMinimizedControl;
+begin
+   FMinimizedControl.Hide;
+   header.Parent:=self;
+   header.UpdateHeaderControls;
+   FMinimizedControl.Parent:=nil;
+   FreeAndNil(DockMaster.FOverlappingForm);
+end;
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5281,21 +5643,24 @@
 begin
   if csDestroying in ComponentState then exit;
   NewCaption:='';
-  for i:=0 to ControlCount-1 do begin
-    Child:=Controls[i];
-    if Child=Exclude then continue;
-    if (Child.HostDockSite=Self) or (Child is TAnchorDockHostSite)
-    or (Child is TAnchorDockPageControl) then begin
-      if NewCaption<>'' then
-        NewCaption:=NewCaption+',';
-      NewCaption:=NewCaption+Child.Caption;
+  if FMinimized then
+    NewCaption:=FMinimizedControl.Caption
+  else
+    for i:=0 to ControlCount-1 do begin
+      Child:=Controls[i];
+      if Child=Exclude then continue;
+      if (Child.HostDockSite=Self) or (Child is TAnchorDockHostSite)
+      or (Child is TAnchorDockPageControl) then begin
+        if NewCaption<>'' then
+          NewCaption:=NewCaption+',';
+        NewCaption:=NewCaption+Child.Caption;
+      end;
     end;
-  end;
   OldCaption:=Caption;
   Caption:=NewCaption;
   //debugln(['TAnchorDockHostSite.UpdateDockCaption Caption="',Caption,'" NewCaption="',NewCaption,'" HasParent=',Parent<>nil,' ',DbgSName(Header)]);
-  if ((Parent=nil) and DockMaster.HideHeaderCaptionFloatingControl)
-  or (not DockMaster.ShowHeaderCaption) then
+  if {((Parent=nil) and DockMaster.HideHeaderCaptionFloatingControl)
+  or (not DockMaster.ShowHeaderCaption)}false then
     Header.Caption:=''
   else
     Header.Caption:=Caption;
@@ -5306,9 +5671,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm));
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5339,7 +5703,8 @@
   end;
 
   CanDock:=(Client is TAnchorDockHostSite)
-           and not DockMaster.AutoFreedIfControlIsRemoved(Self,Client);
+           and not DockMaster.AutoFreedIfControlIsRemoved(Self,Client)
+           and not FMinimized;
   //debugln(['TAnchorDockHostSite.GetSiteInfo ',DbgSName(Self),' ',dbgs(BoundsRect),' ',Caption,' CanDock=',CanDock,' PtIn=',PtInRect(InfluenceRect,MousePos)]);
 
   if Assigned(OnGetSiteInfo) then
@@ -5362,9 +5727,33 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+const
+OppositeAlign: array[TAnchorKind] of TAlign = (
+  alBottom, // akTop,
+  alRight,  // akLeft,
+  alLeft,   // akRight,
+  alTop     // akBottom
+  );
+OppositeAnchorKindAlign: array[TAnchorKind] of TADLHeaderPosition = (
+  adlhpBottom, // akTop,
+  adlhpRight,  // akLeft,
+  adlhpLeft,   // akRight,
+  adlhpTop     // akBottom
+  );
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      NeededHeaderPosition:=OppositeAnchorKindAlign[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5388,10 +5777,16 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderShowing;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  if HeaderNeedsShowing then
-    Header.Parent:=Self
+  if HeaderNeedsShowing then begin
+    Header.Parent:=Self;
+    Header.MinimizeButton.Visible:=(DockMaster.DockSitesCanBeMinimized and CanBeMinimized(Splitter,SplitterAnchorKind))or FMinimized;
+    Header.MinimizeButton.Parent:=Header;
+  end
   else
     Header.Parent:=nil;
 end;
@@ -5432,7 +5827,7 @@
   if (SiteType=adhstOneControl) and (OneControl<>nil)
   and (not (OneControl is TAnchorDockHostSite)) then begin
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.Name:=OneControl.Name;
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if (SiteType in [adhstLayout,adhstOneControl]) then begin
@@ -5450,7 +5845,7 @@
         Splitter.SaveLayout(ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if SiteType=adhstPages then begin
     LayoutNode.NodeType:=adltnPages;
@@ -5461,7 +5856,7 @@
         Site.SaveLayout(LayoutTree,ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else
     LayoutNode.NodeType:=adltnNone;
@@ -5476,6 +5871,9 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
+  fMinimization:=false;
+  FMinimizedControl:=Nil;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5490,13 +5888,13 @@
 end;
 
 destructor TAnchorDockHostSite.Destroy;
-//var i: Integer;
+var i: Integer;
 begin
-  //debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
-  {for i:=0 to ComponentCount-1 do
+  debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
+  for i:=0 to ComponentCount-1 do
     debugln(['TAnchorDockHostSite.Destroy Component ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   for i:=0 to ControlCount-1 do
-    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);}
+    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);
   FreePages;
   inherited Destroy;
 end;
@@ -5562,13 +5960,34 @@
 end;
 
 procedure TAnchorDockHeader.CloseButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
 begin
-  if Parent is TAnchorDockHostSite then begin
-    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(Parent),true);
-    TAnchorDockHostSite(Parent).CloseSite;
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
   end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(HeaderParent),true);
+    HeaderParent.CloseSite;
+  end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
+begin
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
+  end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    HeaderParent.MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5640,6 +6059,13 @@
       r.Right:=CloseButton.Left-1;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+1
+    else
+      r.Right:=MinimizeButton.Left-1;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,25 +6154,102 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
   X, Y: Integer);
+var
+  SiteMinimized:Boolean;
 begin
   inherited MouseDown(Button, Shift, X, Y);
-  if (Button=mbLeft) and DockMaster.AllowDragging then
-    DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
+  SiteMinimized:=False;
+  fUseTimer:=false;
+  StopMouseNoMoveTimer;
+  if Parent is TAnchorDockHostSite then
+    SiteMinimized:=(Parent as TAnchorDockHostSite).FMinimized;
+  if SiteMinimized then begin
+    DoMouseNoMoveTimer(nil);
+  end else
+    begin
+      if parent<>nil then
+        if DockMaster.FOverlappingForm<>nil then
+          //if parent=DockMaster.FOverlappingForm.Panel then
+            DockMaster.HideOverlappingForm(nil);
+      if (Button=mbLeft) and (DockMaster.AllowDragging) and (DockMaster.FOverlappingForm=nil) then
+        DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
+    end;
 end;
 
+procedure  TAnchorDockHeader.MouseMove(Shift: TShiftState; X,Y: Integer);
+begin
+  inherited MouseMove(Shift, X, Y);
+  if parent<>nil then
+    if parent is TAnchorDockHostSite then
+      if (parent as TAnchorDockHostSite).FMinimized then
+        if DockMaster.FOverlappingForm=nil then
+          if FMouseTimeStartX=EmptyMouseTimeStartX then
+            StartMouseNoMoveTimer(X, Y)
+          else begin
+            if (abs(FMouseTimeStartX-X)>MouseNoMoveDelta)or(abs(FMouseTimeStartY-Y)>MouseNoMoveDelta)then
+            StopMouseNoMoveTimer;
+          end;
+  if (parent is TAnchorDockHostSite)and(DockMaster.FOverlappingForm=nil)then
+    fUseTimer:=true;
+end;
+
+procedure TAnchorDockHeader.MouseLeave;
+begin
+  inherited;
+  StopMouseNoMoveTimer;
+end;
+
+procedure TAnchorDockHeader.StartMouseNoMoveTimer(X, Y: Integer);
+begin
+  if fUseTimer then begin
+    if DockTimer.Enabled then DockTimer.Enabled:=false;
+    DockTimer.Interval:=MouseNoMoveTime;
+    DockTimer.OnTimer:=@DoMouseNoMoveTimer;
+    DockTimer.Enabled:=true;
+  end;
+end;
+
+procedure TAnchorDockHeader.StopMouseNoMoveTimer;
+begin
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  DockTimer.OnTimer:=nil;
+  DockTimer.Enabled:=false;
+end;
+
+procedure TAnchorDockHeader.DoMouseNoMoveTimer(Sender: TObject);
+begin
+  StopMouseNoMoveTimer;
+  //if fUseTimer then
+    if parent<>nil then
+      if parent is TAnchorDockHostSite then
+        if (parent as TAnchorDockHostSite).FMinimized then
+          (parent as TAnchorDockHostSite).ShowMinimizedControl;
+end;
+
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alTop;
       CloseButton.Align:=alTop;
+    end;
   end else begin
-    if CloseButton<>nil then
+    if CloseButton<>nil then begin
+      MinimizeButton.Align:=alRight;
       CloseButton.Align:=alRight;
+    end;
   end;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
@@ -5787,9 +6290,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,11 +6302,23 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
   PopupMenu:=DockMaster.GetPopupMenu;
   fFocused:=false;
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  fUseTimer:=true;
 end;
 
 { TAnchorDockCloseButton }
@@ -5844,6 +6359,44 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMinButtonNormal;
+    if not IsEnabled then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonDisabled{$ELSE}twMinButtonDisabled{$ENDIF}
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonPushed{$ELSE}twMinButtonPushed{$ENDIF}
+    else
+    if FState = bsHot then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonHot{$ELSE}twMinButtonHot{$ENDIF}
+    else
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF};
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails({$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF})) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6213,6 +6766,9 @@
   ClientRectChanged:=(WidthDiff<>0) or (HeightDiff<>0);
   if ClientRectChanged or PreferredSiteSizeAsSiteMinimum then
     AlignChilds;
+  if ClientRectChanged then
+    if DockMaster.FOverlappingForm<>nil then
+      DockMaster.HideOverlappingForm(nil);
 end;
 
 procedure TAnchorDockManager.SaveToStream(Stream: TStream);
@@ -6505,32 +7061,58 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
@@ -6560,14 +7142,47 @@
   end;
 end;
 
+function TAnchorDockSplitter.GetSpliterBoundsWithUnminimizedDockSites:TRect;
+var
+  NewLeft, NewTop: Integer;
+begin
+  if ResizeAnchor in [akLeft,akRight] then
+  begin
+    if DockParentClientSize.cx> 0 then
+    begin
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+      else
+        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+      NewTop := Top;
+    end;
+  end else
+  begin
+    if DockParentClientSize.cy> 0 then
+    begin
+      NewLeft := Left;
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewTop := Round(FPercentPosition*Parent.ClientHeight)
+      else
+        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    end;
+  end;
+  result:=Rect(NewLeft,NewTop,NewLeft+Width,NewTop+Height);
+end;
+
 procedure TAnchorDockSplitter.SaveLayout(
   LayoutNode: TAnchorDockLayoutTreeNode);
+var
+  NewLeft, NewTop: Integer;
 begin
   if ResizeAnchor in [akLeft,akRight] then
     LayoutNode.NodeType:=adltnSplitterVertical
   else
     LayoutNode.NodeType:=adltnSplitterHorizontal;
-  LayoutNode.Assign(Self);
+  LayoutNode.Assign(Self,false,false);
+  if not Enabled then begin
+    LayoutNode.BoundsRect:=GetSpliterBoundsWithUnminimizedDockSites;
+  end
 end;
 
 function TAnchorDockSplitter.HasOnlyOneSibling(Side: TAnchorKind; MinPos,
@@ -6645,7 +7260,7 @@
 begin
   inherited MouseDown(Button, Shift, X, Y);
   ATabIndex := IndexOfPageAt(X, Y);
-  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) then
+  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) and (DockMaster.FOverlappingForm=nil) then
   begin
     APage:=Page[ATabIndex];
     if (APage.ControlCount>0) and (APage.Controls[0] is TAnchorDockHostSite) then
@@ -6782,6 +7397,20 @@
   PopupMenu:=DockMaster.GetPopupMenu;
 end;
 
+{ TAnchorDockOverlappingForm }
+
+constructor TAnchorDockOverlappingForm.CreateNew(AOwner: TComponent; Num: Integer = 0);
+begin
+  inherited;
+  BorderStyle:=bsNone;
+  AnchorDockHostSite:=nil;
+  Panel:=TPanel.Create(self);
+  Panel.BorderStyle:=bsSingle;
+  Panel.Align:=alClient;
+  Panel.Parent:=self;
+  Panel.Visible:=true;
+end;
+
 { TAnchorDockPage }
 
 procedure TAnchorDockPage.UpdateDockCaption(Exclude: TControl);
@@ -6835,9 +7464,11 @@
 
 initialization
   DockMaster:=TAnchorDockMaster.Create(nil);
+  DockTimer:=TTimer.Create(nil);
 
 finalization
   FreeAndNil(DockMaster);
+  FreeAndNil(DockTimer);
 
 end.
 
Index: components/anchordocking/anchordockoptionsdlg.lfm
===================================================================
--- components/anchordocking/anchordockoptionsdlg.lfm	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.lfm	(working copy)
@@ -1,11 +1,13 @@
 object AnchorDockOptionsFrame: TAnchorDockOptionsFrame
   Left = 0
-  Height = 482
+  Height = 567
   Top = 0
-  Width = 416
-  ClientHeight = 482
-  ClientWidth = 416
+  Width = 490
+  ClientHeight = 567
+  ClientWidth = 490
+  DesignTimePPI = 113
   OnClick = FrameClick
+  ParentFont = False
   TabOrder = 0
   DesignLeft = 513
   DesignTop = 189
@@ -12,14 +14,15 @@
   object DragThresholdLabel: TLabel
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
-    Left = 10
-    Height = 13
-    Top = 10
-    Width = 111
-    BorderSpacing.Left = 10
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 12
+    Width = 122
+    BorderSpacing.Left = 12
+    BorderSpacing.Top = 12
     Caption = 'DragThresholdLabel'
     ParentColor = False
+    ParentFont = False
   end
   object DragThresholdTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdLabel
@@ -27,15 +30,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 23
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 31
+    Width = 466
     Max = 20
     OnChange = DragThresholdTrackBarChange
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Right = 10
+    BorderSpacing.Right = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 1
@@ -46,12 +50,13 @@
     AnchorSideTop.Control = DragThresholdLabel
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
-    Left = 127
-    Height = 23
-    Top = 5
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 141
+    Height = 27
+    Top = 8
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 20
+    ParentFont = False
     TabOrder = 0
     Visible = False
   end
@@ -59,13 +64,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = DragThresholdTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 79
-    Width = 103
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 97
+    Width = 112
+    BorderSpacing.Top = 12
     Caption = 'SplitterWidthLabel'
     ParentColor = False
+    ParentFont = False
   end
   object SplitterWidthTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdTrackBar
@@ -73,14 +79,15 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 92
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 116
+    Width = 466
     Min = 1
     OnChange = SplitterWidthTrackBarChange
     Position = 1
     Anchors = [akTop, akLeft, akRight]
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 3
@@ -89,12 +96,13 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = SplitterWidthTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 142
-    Width = 160
-    BorderSpacing.Top = 4
+    Left = 12
+    Height = 23
+    Top = 175
+    Width = 169
+    BorderSpacing.Top = 5
     Caption = 'ScaleOnResizeCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 4
@@ -103,12 +111,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 166
-    Width = 149
+    Left = 12
+    Height = 23
+    Top = 198
+    Width = 160
     Caption = 'ShowHeaderCheckBox'
     OnChange = ShowHeaderCheckBoxChange
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 5
@@ -117,12 +126,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ShowHeaderCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 190
-    Width = 191
-    BorderSpacing.Left = 15
+    Left = 30
+    Height = 23
+    Top = 221
+    Width = 208
+    BorderSpacing.Left = 18
     Caption = 'ShowHeaderCaptionCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 6
@@ -131,11 +141,12 @@
     AnchorSideLeft.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 214
-    Width = 249
+    Left = 30
+    Height = 23
+    Top = 244
+    Width = 272
     Caption = 'HideHeaderCaptionForFloatingCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 7
@@ -147,15 +158,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 122
+    Left = 136
     Height = 27
-    Top = 286
-    Width = 284
+    Top = 313
+    Width = 342
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 6
-    BorderSpacing.Right = 10
-    ItemHeight = 0
+    BorderSpacing.Left = 7
+    BorderSpacing.Right = 12
+    ItemHeight = 19
     OnDrawItem = HeaderStyleComboBoxDrawItem
+    ParentFont = False
     Style = csDropDownList
     TabOrder = 10
   end
@@ -163,23 +175,25 @@
     AnchorSideLeft.Control = ShowHeaderCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrCenter
-    Left = 20
-    Height = 13
-    Top = 293
-    Width = 96
-    BorderSpacing.Left = 10
+    Left = 24
+    Height = 19
+    Top = 317
+    Width = 105
+    BorderSpacing.Left = 12
     Caption = 'HeaderStyleLabel'
     ParentColor = False
+    ParentFont = False
   end
   object FlattenHeadersCheckBox: TCheckBox
     AnchorSideLeft.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 238
-    Width = 164
+    Left = 30
+    Height = 23
+    Top = 267
+    Width = 175
     Caption = 'FlattenHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 8
@@ -188,11 +202,12 @@
     AnchorSideLeft.Control = FlattenHeadersCheckBox
     AnchorSideTop.Control = FlattenHeadersCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 262
-    Width = 154
+    Left = 30
+    Height = 23
+    Top = 290
+    Width = 164
     Caption = 'FilledHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 9
@@ -201,11 +216,12 @@
     AnchorSideLeft.Control = FilledHeadersCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 313
-    Width = 175
+    Left = 30
+    Height = 23
+    Top = 340
+    Width = 189
     Caption = 'HighlightFocusedCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 11
@@ -215,13 +231,14 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = SplitterWidthLabel
     AnchorSideTop.Side = asrCenter
-    Left = 119
-    Height = 23
-    Top = 74
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 131
+    Height = 27
+    Top = 93
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 10
     MinValue = 1
+    ParentFont = False
     TabOrder = 2
     Value = 1
     Visible = False
@@ -228,15 +245,16 @@
   end
   object HeaderAlignTopLabel: TLabel
     AnchorSideLeft.Control = DragThresholdLabel
-    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Control = DockSitesCanBeMinimized
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 347
-    Width = 117
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 398
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignTopLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignTopTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -244,10 +262,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 360
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 417
+    Width = 466
     Frequency = 10
     Max = 150
     OnChange = HeaderAlignTopTrackBarChange
@@ -254,7 +272,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 13
@@ -264,12 +283,13 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignTopLabel
     AnchorSideTop.Side = asrCenter
-    Left = 133
-    Height = 23
-    Top = 342
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 394
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 150
+    ParentFont = False
     TabOrder = 12
     Visible = False
   end
@@ -277,13 +297,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = HeaderAlignTopTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 417
-    Width = 120
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 484
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignLeftLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignLeftTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -291,10 +312,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 430
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 503
+    Width = 466
     Frequency = 10
     Max = 200
     OnChange = HeaderAlignLeftTrackBarChange
@@ -301,7 +322,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 15
@@ -311,13 +333,28 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignLeftLabel
     AnchorSideTop.Side = asrCenter
-    Left = 136
-    Height = 23
-    Top = 412
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 480
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 200
+    ParentFont = False
     TabOrder = 14
     Visible = False
   end
+  object DockSitesCanBeMinimized: TCheckBox
+    AnchorSideLeft.Control = FilledHeadersCheckBox
+    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Side = asrBottom
+    Left = 30
+    Height = 23
+    Top = 363
+    Width = 185
+    Caption = 'DockSitesCanBeMinimized'
+    ParentFont = False
+    ParentShowHint = False
+    ShowHint = True
+    TabOrder = 16
+  end
 end
Index: components/anchordocking/anchordockoptionsdlg.pas
===================================================================
--- components/anchordocking/anchordockoptionsdlg.pas	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.pas	(working copy)
@@ -37,6 +37,7 @@
     HeaderStyleLabel: TLabel;
     HideHeaderCaptionForFloatingCheckBox: TCheckBox;
     HighlightFocusedCheckBox: TCheckBox;
+    DockSitesCanBeMinimized: TCheckBox;
     ScaleOnResizeCheckBox: TCheckBox;
     ShowHeaderCaptionCheckBox: TCheckBox;
     ShowHeaderCheckBox: TCheckBox;
@@ -202,7 +203,7 @@
 
       HeaderAlignTopSpinEdit.Visible:=true;
       HeaderAlignTopTrackBar.Visible:=false;
-      HeaderAlignTopSpinEdit.AnchorToNeighbour(akTop,6,HighlightFocusedCheckBox);
+      HeaderAlignTopSpinEdit.AnchorToNeighbour(akTop,6,DockSitesCanBeMinimized);
       HeaderAlignTopLabel.AnchorVerticalCenterTo(HeaderAlignTopSpinEdit);
       UpdateHeaderAlignTopLabel;
 
@@ -299,6 +300,7 @@
   HeaderStyleLabel.Enabled:=HasHeaders;
   HeaderStyleComboBox.Enabled:=HasHeaders;
   HighlightFocusedCheckBox.Enabled:=HasHeaders;
+  DockSitesCanBeMinimized.Enabled:=HasHeaders;
 end;
 
 constructor TAnchorDockOptionsFrame.Create(TheOwner: TComponent);
@@ -356,6 +358,7 @@
   TheSettings.HeaderFilled:=FilledHeadersCheckBox.Checked;
   TheSettings.HeaderStyle:=TADHeaderStyle(HeaderStyleComboBox.ItemIndex);
   TheSettings.HeaderHighlightFocused:=HighlightFocusedCheckBox.Checked;
+  TheSettings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized.Checked;
 end;
 
 procedure TAnchorDockOptionsFrame.LoadFromSettings(
@@ -429,6 +432,10 @@
   HighlightFocusedCheckBox.Checked:=TheSettings.HeaderHighlightFocused;
   HighlightFocusedCheckBox.Caption:=adrsHighlightFocused;
   HighlightFocusedCheckBox.Hint:=adrsHighlightFocusedHint;
+
+  DockSitesCanBeMinimized.Checked:=TheSettings.DockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Caption:=adrsDockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Hint:=adrsDockSitesCanBeMinimizedHint;
 end;
 
 end.
Index: components/anchordocking/anchordockpanel.pas
===================================================================
--- components/anchordocking/anchordockpanel.pas	(revision 59428)
+++ components/anchordocking/anchordockpanel.pas	(working copy)
@@ -55,7 +55,7 @@
   begin
 
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,false);
     LayoutNode.Name:={OneControl.}Name;
 
     TAnchorDockHostSite(OneControl).SaveLayout(LayoutTree,LayoutNode);
Index: components/anchordocking/anchordockstorage.pas
===================================================================
--- components/anchordocking/anchordockstorage.pas	(revision 59428)
+++ components/anchordocking/anchordockstorage.pas	(working copy)
@@ -64,6 +64,7 @@
     FTabPosition: TTabPosition;
     FWindowState: TWindowState;
     FControlLocation: TADLControlLocation;
+    FMinimized: Boolean;
     function GetAnchors(Site: TAnchorKind): string;
     function GetBottom: integer;
     function GetHeight: integer;
@@ -90,6 +91,7 @@
     procedure SetTop(const AValue: integer);
     procedure SetWidth(const AValue: integer);
     procedure SetWindowState(const AValue: TWindowState);
+    procedure SetMinimized(const AValue: boolean);
   public
     constructor Create;
     destructor Destroy; override;
@@ -96,7 +98,7 @@
     procedure Clear;
     function IsEqual(Node: TAnchorDockLayoutTreeNode): boolean;
     procedure Assign(Node: TAnchorDockLayoutTreeNode); overload;
-    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean=false); overload;
+    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean); overload;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
     procedure LoadFromConfig(Path: string; Config: TRttiXMLConfig); overload;
     procedure SaveToConfig(Config: TConfigStorage); overload;
@@ -106,7 +108,7 @@
     procedure CheckConsistency; virtual;
 
     // simplifying
-    procedure Simplify(ExistingNames: TStrings);
+    procedure Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
     procedure DeleteNode(ChildNode: TAnchorDockLayoutTreeNode);
     function FindNodeBoundSplitter(ChildNode: TAnchorDockLayoutTreeNode;
                                    Side: TAnchorKind): TAnchorDockLayoutTreeNode;
@@ -135,6 +137,7 @@
     property Monitor: integer read FMonitor write SetMonitor;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property TabPosition: TTabPosition read FTabPosition write SetTabPosition;
+    property Minimized: Boolean read FMinimized write SetMinimized;
     function Count: integer;
     function IsSplitter: boolean;
     function IsRootWindow: boolean;
@@ -988,6 +991,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockLayoutTreeNode.SetMinimized(const AValue: boolean);
+begin
+  if FMinimized=AValue then exit;
+  FMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockLayoutTreeNode.SetTop(const AValue: integer);
 begin
   if Top=AValue then exit;
@@ -1084,6 +1094,7 @@
   BoundSplitterPos:=Node.BoundSplitterPos;
   WorkAreaRect:=Node.WorkAreaRect;
   Monitor:=Node.Monitor;
+  Minimized:=Node.Minimized;
   for a:=low(TAnchorKind) to high(TAnchorKind) do
     Anchors[a]:=Node.Anchors[a];
   while Count>Node.Count do Nodes[Count-1].Free;
@@ -1098,9 +1109,10 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean=false);
+procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean);
 var
   AnchorControl: TControl;
+  ParentForm:TCustomForm;
   a: TAnchorKind;
 begin
   Name:=AControl.Name;
@@ -1109,12 +1121,18 @@
   else
     BoundsRect:=AControl.BoundsRect;
   Align:=AControl.Align;
+  Minimized:=AMinimized;
   if (AControl.Parent=nil) and (AControl is TCustomForm) then begin
     WindowState:=TCustomForm(AControl).WindowState;
     Monitor:=TCustomForm(AControl).Monitor.MonitorNum;
     WorkAreaRect:=TCustomForm(AControl).Monitor.WorkareaRect;
-  end else
-    WindowState:=GetParentForm(AControl).WindowState;
+  end else begin
+    ParentForm:=GetParentForm(AControl);
+    if assigned(ParentForm) then
+      WindowState:=ParentForm.WindowState
+    else
+      WindowState:=wsNormal;
+  end;
   if AControl is TCustomTabControl then
     TabPosition:=TCustomTabControl(AControl).TabPosition
   else
@@ -1137,6 +1155,7 @@
   Clear;
   Name:=Config.GetValue('Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue('Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue('Minimized',false);
   Left:=Config.GetValue('Bounds/Left',0);
   Top:=Config.GetValue('Bounds/Top',0);
   Width:=Config.GetValue('Bounds/Width',0);
@@ -1171,6 +1190,7 @@
   Clear;
   Name:=Config.GetValue(Path+'Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue(Path+'Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue(Path+'Minimized',false);
   Left:=Config.GetValue(Path+'Bounds/Left',0);
   Top:=Config.GetValue(Path+'Bounds/Top',0);
   Width:=Config.GetValue(Path+'Bounds/Width',0);
@@ -1219,6 +1239,7 @@
                                           ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue('Header/TabPosition',ADLTabPostionNames[TabPosition],
                                              ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue('Minimized',Minimized,False);
   Config.SetDeleteValue('Monitor',Monitor,0);
   Config.SetDeleteValue('ChildCount',Count,0);
   for i:=1 to Count do begin
@@ -1252,6 +1273,7 @@
                                                ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue(Path+'Header/TabPosition',ADLTabPostionNames[TabPosition],
                                                   ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue(Path+'Minimized',Minimized,False);
   Config.SetDeleteValue(Path+'Monitor',Monitor,0);
   Config.SetDeleteValue(Path+'ChildCount',Count,0);
   for i:=1 to Count do
@@ -1397,7 +1419,7 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings);
+procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
 { Simplification rules:
    1. Control nodes without existing name are deleted.
    2. Empty layouts and pages are deleted
@@ -1406,16 +1428,18 @@
 var
   i: Integer;
   ChildNode: TAnchorDockLayoutTreeNode;
+  NodeMinimized:boolean;
 begin
   // simplify children
   i:=Count-1;
   while i>=0 do begin
     ChildNode:=Nodes[i];
-    ChildNode.Simplify(ExistingNames);
+    NodeMinimized:=ParentMinimized or ChildNode.Minimized;
+    ChildNode.Simplify(ExistingNames,NodeMinimized);
 
     if (ChildNode.NodeType=adltnControl) then begin
       // leaf node => check if there is a control
-      if (ChildNode.Name='') or (ExistingNames.IndexOf(ChildNode.Name)<0) then
+      if (ChildNode.Name='') or ((ExistingNames.IndexOf(ChildNode.Name)<0) and (not NodeMinimized)) then
         DeleteNode(ChildNode);
     end else if ChildNode.IsSplitter then begin
       // splitter
@@ -1424,7 +1448,7 @@
         ChildNode[0].Free;
     end else if ChildNode.NodeType=adltnCustomSite then begin
       // custom dock site
-    end else if ChildNode.Count=0 then begin
+    end else if (ChildNode.Count=0)and(not NodeMinimized) then begin
       // inner node without child => delete
       DeleteNode(ChildNode);
     end else if (ChildNode.Count=1)
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59428)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';
@@ -82,6 +83,8 @@
   adrsFilledHeadersHint = 'Fill headers of docked controls';
   adrsHighlightFocused = 'Highlight focused';
   adrsHighlightFocusedHint = 'Highlight header of focused docked control';
+  adrsDockSitesCanBeMinimized = 'Dock sites can be minimized';
+  adrsDockSitesCanBeMinimizedHint = 'Dock sites can be minimized';
 
 implementation
 
Index: components/anchordocking/design/anchordesktopoptions.pas
===================================================================
--- components/anchordocking/design/anchordesktopoptions.pas	(revision 59428)
+++ components/anchordocking/design/anchordesktopoptions.pas	(working copy)
@@ -272,7 +272,7 @@
         // custom dock site
         LayoutNode:=FTree.NewNode(FTree.Root);
         LayoutNode.NodeType:=adltnCustomSite;
-        LayoutNode.Assign(AForm);
+        LayoutNode.Assign(AForm,false,false);
         // can have one normal dock site
         Site:=TAnchorDockManager(AForm.DockManager).GetChildSite;
         if Site<>nil then begin
@@ -287,7 +287,7 @@
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    FTree.Root.Simplify(VisibleControls);
+    FTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;

<?xml version="1.0" encoding="utf-8"?>
<CONFIG>
  <MainConfig>
    <Nodes ChildCount="2">
      <Item1 Name="MainIDE" Type="CustomSite" ChildCount="1">
        <Bounds Top="50" Left="100" Width="600" Height="434">
          <WorkArea>
            <Rect Right="1920" Bottom="1036"/>
          </WorkArea>
        </Bounds>
        <Item1 Name="AnchorDockSite3" Type="Layout" ChildCount="3">
          <Bounds Top="60" Width="600" Height="350" SplitterPos="55"/>
          <Anchors Align="Bottom"/>
          <Item1 Name="ObjectInspector" Type="Control">
            <Bounds Width="296" Height="350"/>
            <Anchors Right="AnchorDockSplitter2"/>
          </Item1>
          <Item2 Name="AnchorDockSplitter2" Type="SplitterVertical">
            <Bounds Left="296" Width="4" Height="350"/>
          </Item2>
          <Item3 Name="SourceEditor1" Type="Control">
            <Bounds Left="300" Width="300" Height="350"/>
            <Anchors Left="AnchorDockSplitter2"/>
          </Item3>
        </Item1>
      </Item1>
      <Item2 Name="Messages" Type="Control">
        <Bounds Top="548" Left="208" Width="350" Height="100">
          <WorkArea>
            <Rect Right="1920" Bottom="1036"/>
          </WorkArea>
        </Bounds>
      </Item2>
    </Nodes>
  </MainConfig>
  <Settings DockSitecCanBeMinimized="True"/>
</CONFIG>

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59428)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -109,6 +109,12 @@
 const ADAutoSizingReason = 'TAnchorDockMaster Delayed';
 {$ENDIF}
 
+const EmptyMouseTimeStartX=low(Integer);
+      MouseNoMoveDelta=5;
+      MouseNoMoveTime=500;
+      HideOverlappingFormByMouseLoseTime=500;
+      ButtonBorderSpacingAround=4;
+
 type
   TAnchorDockHostSite = class;
 
@@ -123,6 +129,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +147,13 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
+    fUseTimer:Boolean;
+    FMouseTimeStartX,FMouseTimeStartY:Integer;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -147,6 +165,11 @@
           PreferredHeight: integer; WithThemeSpace: Boolean); override;
     procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X,
              Y: Integer); override;
+    procedure MouseMove(Shift: TShiftState; X,Y: Integer); override;
+    procedure MouseLeave;  override;
+    procedure StartMouseNoMoveTimer(X, Y: Integer);
+    procedure StopMouseNoMoveTimer;
+    procedure DoMouseNoMoveTimer(Sender: TObject);
     procedure UpdateHeaderControls;
     procedure SetAlign(Value: TAlign); override;
     procedure DoOnShowHint(HintInfo: PHintInfo); override;
@@ -154,6 +177,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -190,6 +214,7 @@
     procedure SetBoundsKeepDockBounds(ALeft, ATop, AWidth, AHeight: integer); // movement for scaling keeps the DockBounds
     function SideAnchoredControlCount(Side: TAnchorKind): integer;
     function HasAnchoredControls: boolean;
+    function GetSpliterBoundsWithUnminimizedDockSites:TRect;
     procedure SaveLayout(LayoutNode: TAnchorDockLayoutTreeNode);
     function HasOnlyOneSibling(Side: TAnchorKind; MinPos, MaxPos: integer): TControl;
     property DockRestoreBounds: TRect read FDockRestoreBounds write FDockRestoreBounds;
@@ -241,6 +266,14 @@
   end;
   TAnchorDockPageControlClass = class of TAnchorDockPageControl;
 
+
+  TAnchorDockOverlappingForm = class(TCustomForm)
+  public
+    AnchorDockHostSite:TAnchorDockHostSite;
+    Panel:TPanel;
+    constructor CreateNew(AOwner: TComponent; Num: Integer = 0); override;
+  end;
+
   { TAnchorDockHostSite
     This form is the dockhostsite for all controls.
     When docked together they build a tree structure with the docked controls
@@ -262,7 +295,10 @@
     FPages: TAnchorDockPageControl;
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
-    fUpdateLayout: integer;
+    fUpdateLayout: Integer;
+    FMinimized: Boolean;
+    fMinimization: Boolean;
+    FMinimizedControl: TControl;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +355,10 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
+    procedure AsyncMinimizeSite(Data: PtrInt);
+    procedure ShowMinimizedControl;
+    procedure HideMinimizedControl;
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -329,6 +369,7 @@
     procedure UpdateDockCaption(Exclude: TControl = nil); override;
     procedure UpdateHeaderAlign;
     procedure UpdateHeaderShowing;
+    function CanBeMinimized(out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
     procedure BeginUpdateLayout;
     procedure EndUpdateLayout;
     function UpdatingLayout: boolean;
@@ -431,6 +472,7 @@
     FShowHeader: boolean;
     FShowHeaderCaption: boolean;
     FSplitterWidth: integer;
+    FDockSitecCanBeMinimized: boolean;
     procedure SetAllowDragging(AValue: boolean);
     procedure SetDockOutsideMargin(AValue: integer);
     procedure SetDockParentMargin(AValue: integer);
@@ -448,6 +490,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitecCanBeMinimized(AValue: boolean);
   public
     property DragTreshold: integer read FDragTreshold write SetDragTreshold;
     property DockOutsideMargin: integer read FDockOutsideMargin write SetDockOutsideMargin;
@@ -466,6 +509,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused;
+    property DockSitesCanBeMinimized: boolean read FDockSitecCanBeMinimized write SetDockSitecCanBeMinimized;
     procedure IncreaseChangeStamp; inline;
     property ChangeStamp: integer read FChangeStamp;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
@@ -502,6 +546,7 @@
     FHeaderFlatten: boolean;
     FHeaderFilled: boolean;
     FHeaderHighlightFocused: boolean;
+    FDockSitesCanBeMinimized: boolean;
     FIdleConnected: Boolean;
     FManagerClass: TAnchorDockManagerClass;
     FOnCreateControl: TADCreateControlEvent;
@@ -531,6 +576,7 @@
     fPopupMenu: TPopupMenu;
     // Used by RestoreLayout:
     WorkArea, SrcWorkArea: TRect;
+    FOverlappingForm:TAnchorDockOverlappingForm;
 
     function GetControls(Index: integer): TControl;
     function GetLocalizedHeaderHint: string;
@@ -541,6 +587,9 @@
     function GetNodeSite(Node: TAnchorDockLayoutTreeNode): TAnchorDockHostSite;
     procedure MapTreeToControls(Tree: TAnchorDockLayoutTree);
     function RestoreLayout(Tree: TAnchorDockLayoutTree; Scale: boolean): boolean;
+    procedure SetMinimizedState(Tree: TAnchorDockLayoutTree);
+    procedure UpdateHeaders;
+    procedure SetnodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
     procedure EnableAllAutoSizing;
     procedure ClearLayoutProperties(AControl: TControl; NewAlign: TAlign = alClient);
     procedure PopupMenuPopup(Sender: TObject);
@@ -561,6 +610,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitesCanBeMinimized(AValue: boolean);
 
     procedure SetShowMenuItemShowHeader(AValue: boolean);
     procedure SetupSite(Site: TWinControl; ANode: TAnchorDockLayoutTreeNode;
@@ -584,8 +634,12 @@
     procedure SetHideHeaderCaptionFloatingControl(const AValue: boolean);
     procedure SetSplitterWidth(const AValue: integer);
     procedure OnIdle(Sender: TObject; var Done: Boolean);
+    procedure StartHideOverlappingTimer;
+    procedure StopHideOverlappingTimer;
     procedure AsyncSimplify({%H-}Data: PtrInt);
   public
+    procedure ShowOverlappingForm;
+    procedure HideOverlappingForm(Sender: TObject);
     constructor Create(AOwner: TComponent); override;
     destructor Destroy; override;
     function FullRestoreLayout(Tree: TAnchorDockLayoutTree; Scale: Boolean): Boolean;
@@ -680,6 +734,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten default true;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled default true;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused default false;
+    property DockSitesCanBeMinimized: boolean read FDockSitesCanBeMinimized write SetDockSitesCanBeMinimized default false;
 
     property SplitterWidth: integer read FSplitterWidth write SetSplitterWidth default 4;
     property ScaleOnResize: boolean read FScaleOnResize write SetScaleOnResize default true; // scale children when resizing a site
@@ -698,8 +753,14 @@
 
 var
   DockMaster: TAnchorDockMaster = nil;
+  DockTimer: TTimer = nil;
 
+  PreferredButtonWidth:integer=-1;
+  PreferredButtonHeight:integer=-1;
+
+
 const
+  HardcodedButtonSize:integer=13;
   ADHeaderStyleNames: array[TADHeaderStyle] of string = (
     'Frame3D',
     'Line',
@@ -970,6 +1031,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -1361,6 +1443,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockSettings.SetDockSitecCanBeMinimized(AValue: boolean);
+begin
+  if FDockSitecCanBeMinimized=AValue then Exit;
+  FDockSitecCanBeMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockSettings.Assign(Source: TAnchorDockSettings);
 begin
   FAllowDragging := Source.FAllowDragging;
@@ -1381,6 +1470,7 @@
   FShowHeaderCaption := Source.FShowHeaderCaption;
   FSplitterWidth := Source.FSplitterWidth;
   FHeaderHighlightFocused:=Source.FHeaderHighlightFocused;
+  FDockSitecCanBeMinimized:=Source.FDockSitecCanBeMinimized;
 end;
 
 procedure TAnchorDockSettings.IncreaseChangeStamp;
@@ -1407,6 +1497,7 @@
   HeaderFlatten:=Config.GetValue('HeaderFlatten',true);
   HeaderFilled:=Config.GetValue('HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue('HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue('DockSitecCanBeMinimized',False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1429,6 +1520,7 @@
   Config.SetDeleteValue(Path+'HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue(Path+'HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue(Path+'HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue(Path+'DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
 end;
 
 procedure TAnchorDockSettings.SaveToConfig(Config: TConfigStorage);
@@ -1450,6 +1542,7 @@
   Config.SetDeleteValue('HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue('HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue('HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue('DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1472,6 +1565,7 @@
       and (HeaderFlatten=Settings.HeaderFlatten)
       and (HeaderFilled=Settings.HeaderFilled)
       and (HeaderHighlightFocused=Settings.HeaderHighlightFocused)
+      and (DockSitesCanBeMinimized=Settings.DockSitesCanBeMinimized)
       ;
 end;
 
@@ -1494,6 +1588,7 @@
   HeaderFlatten:=Config.GetValue(Path+'HeaderFlatten',true);
   HeaderFilled:=Config.GetValue(Path+'HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue(Path+'HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue(Path+'DockSitecCanBeMinimized',False);
 end;
 
 { TAnchorDockMaster }
@@ -2021,6 +2116,8 @@
     aHostSite:=TAnchorDockHostSite(Site);
     aHostSite.Header.HeaderPosition:=ANode.HeaderPosition;
     aHostSite.DockRestoreBounds:=NewBounds;
+    //aHostSite.FMinimized:=ANode.Minimized;
+    //we update aHostSite.FMinimized in TAnchorDockMaster.SetMinimizedState
     if (ANode.NodeType<>adltnPages) and (aHostSite.Pages<>nil) then
       aHostSite.FreePages;
   end;
@@ -2040,6 +2137,25 @@
   fTreeNameToDocker[Node.Name]:=Result;
 end;
 
+procedure TAnchorDockMaster.SetNodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
+var
+  HostSite:TAnchorDockHostSite;
+  i:integer;
+begin
+  HostSite:=GetNodeSite(ANode);
+  if Assigned(HostSite) then
+    if HostSite.FMinimized<>ANode.Minimized then
+      Application.QueueAsyncCall(@HostSite.AsyncMinimizeSite,0);
+      //HostSite.MinimizeSite;
+  for i:=0 to ANode.Count-1 do
+    SetnodeMinimizedState(ANode.Nodes[i]);
+end;
+
+procedure TAnchorDockMaster.SetMinimizedState(Tree: TAnchorDockLayoutTree);
+begin
+  SetnodeMinimizedState(Tree.Root);
+end;
+
 function TAnchorDockMaster.RestoreLayout(Tree: TAnchorDockLayoutTree;
   Scale: boolean): boolean;
 
@@ -2193,7 +2309,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -2358,7 +2474,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -2368,6 +2484,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -2422,11 +2539,54 @@
   OptionsChanged;
 end;
 
+procedure TAnchorDockMaster.StartHideOverlappingTimer;
+begin
+  if not DockTimer.Enabled then begin
+    DockTimer.Interval:=HideOverlappingFormByMouseLoseTime;
+    DockTimer.OnTimer:=@HideOverlappingForm;
+    DockTimer.Enabled:=true;
+  end;
+end;
+
+procedure TAnchorDockMaster.StopHideOverlappingTimer;
+begin
+  DockTimer.Enabled:=False;
+  DockTimer.Interval:=0;
+  DockTimer.OnTimer:=nil;
+end;
+
+function IsParentControl(aParent, aControl: TControl): boolean;
+begin
+  while (aControl <> nil) and (aControl.Parent <> nil) do
+  begin
+    if (aControl=aParent) then
+      exit(true);
+    aControl := aControl.Parent;
+  end;
+  result:=aControl=aParent;
+end;
+
+
 procedure TAnchorDockMaster.OnIdle(Sender: TObject; var Done: Boolean);
+var
+  MousePos: TPoint;
+  Bounds:Trect;
 begin
   if Done then ;
-  IdleConnected:=false;
   Restoring:=false;
+  if FOverlappingForm=nil then
+    IdleConnected:=false
+  else begin
+    GetCursorPos(MousePos);
+    Bounds.TopLeft:=FOverlappingForm.ClientToScreen(point(0,0));
+    Bounds.BottomRight:=FOverlappingForm.ClientToScreen(point(FOverlappingForm.Width,FOverlappingForm.Height));
+    if not IsParentControl(FOverlappingForm, GetCaptureControl) then begin
+      if not PtInRect(Bounds,MousePos) then
+          StartHideOverlappingTimer
+        else
+          StopHideOverlappingTimer;
+    end;
+  end;
 end;
 
 procedure TAnchorDockMaster.AsyncSimplify(Data: PtrInt);
@@ -2514,6 +2674,18 @@
   InvalidateHeaders;
 end;
 
+procedure TAnchorDockMaster.SetDockSitesCanBeMinimized(AValue: boolean);
+var
+  i:integer;
+  Site: TAnchorDockHostSite;
+begin
+  if FDockSitesCanBeMinimized=AValue then Exit;
+  FDockSitesCanBeMinimized:=AValue;
+  UpdateHeaders;
+  InvalidateHeaders;
+  EnableAllAutoSizing;
+  OptionsChanged;
+end;
 procedure TAnchorDockMaster.SetScaleOnResize(AValue: boolean);
 begin
   if FScaleOnResize=AValue then Exit;
@@ -2598,6 +2770,9 @@
     if (Site.Header<>nil) then begin
       DisableControlAutoSizing(Site);
       Site.UpdateHeaderShowing;
+      if Site.fminimized then
+        if not AValue then
+          site.MinimizeSite;
     end;
   end;
   EnableAllAutoSizing;
@@ -2668,6 +2843,20 @@
     EnableAllAutoSizing;
 end;
 
+procedure TAnchorDockMaster.ShowOverlappingForm;
+begin
+  FOverlappingForm.Show;
+  IdleConnected:=true;
+end;
+
+procedure TAnchorDockMaster.HideOverlappingForm(Sender: TObject);
+begin
+  StopHideOverlappingTimer;
+  FOverlappingForm.Hide;
+  FOverlappingForm.AnchorDockHostSite.HideMinimizedControl;
+  IdleConnected:=false;
+end;
+
 constructor TAnchorDockMaster.Create(AOwner: TComponent);
 begin
   inherited Create(AOwner);
@@ -2698,14 +2887,14 @@
   FPageClass:=TAnchorDockPage;
   FRestoreLayouts:=TAnchorDockRestoreLayouts.Create;
   FHeaderHighlightFocused:=false;
+  FDockSitesCanBeMinimized:=false;
+  FOverlappingForm:=nil;
 end;
 
 destructor TAnchorDockMaster.Destroy;
 var
   AControl: TControl;
-  {$IFDEF VerboseAnchorDocking}
-  i: Integer;
-  {$ENDIF}
+  i, j: Integer;
 begin
   QueueSimplify:=false;
   FreeAndNil(FRestoreLayouts);
@@ -2727,6 +2916,12 @@
     debugln(['TAnchorDockMaster.Destroy ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   end;
   {$ENDIF}
+  for i:=0 to ComponentCount-1 do begin
+    for j:=0 to ComponentCount-1 do begin
+      if i<>j then
+        TControl(Components[i]).RemoveAllHandlersOfObject(TControl(Components[j]));
+  end;
+  end;
   inherited Destroy;
 end;
 
@@ -2914,6 +3109,7 @@
       raise Exception.Create('TAnchorDockMaster.MakeDockable '+Format(
         adrsNotSupportedHasParent, [DbgSName(AControl), DbgSName(AControl)]));
     end;
+    site.UpdateHeaderShowing;
     if (Site<>nil) and Show then
       MakeVisible(Site,BringToFront);
   finally
@@ -3018,7 +3214,8 @@
   i:=Screen.CustomFormCount-1;
   while i>=0 do begin
     AForm:=GetParentForm(Screen.CustomForms[i]);
-    AForm.Hide;
+    if Assigned(AForm)then
+      AForm.Hide;
     i:=Min(i,Screen.CustomFormCount)-1;
   end;
 
@@ -3062,8 +3259,11 @@
   end;
 end;
 
-function GetParentFormOrDockPanel(Control: TControl): TCustomForm;
+function GetParentFormOrDockPanel(Control: TControl; TopForm:Boolean=true): TCustomForm;
+var
+  oldControl: TControl;
 begin
+  oldControl:=Control;
   while (Control <> nil) and (Control.Parent <> nil) do
   begin
     if (Control is TAnchorDockPanel) then
@@ -3076,6 +3276,18 @@
     Result := TCustomForm(Control)
   else
     Result := nil;
+  if not TopForm then begin
+    if Control is TAnchorDockPanel then
+      exit;
+    Control:=oldControl;
+    while (Control <> nil) and (Control.Parent <> nil) do
+    begin
+      Control := Control.Parent;
+      if (Control is TCustomForm) then
+        Break;
+    end;
+    Result := TCustomForm(Control);
+  end;
 end;
 
 procedure TAnchorDockMaster.SaveMainLayoutToTree(LayoutTree: TAnchorDockLayoutTree);
@@ -3088,12 +3300,12 @@
   AFormOrDockPanel: TWinControl;
   VisibleControls: TStringList;
 
-  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean);
+  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean; AMinimized:boolean);
   begin
     // custom dock site
     LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
     LayoutNode.NodeType:=adltnCustomSite;
-    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel);
+    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel,AMinimized);
     // can have one normal dock site
     if SaveChildren then
     begin
@@ -3124,7 +3336,7 @@
       debugln(['TAnchorDockMaster.SaveMainLayoutToTree AForm=',DbgSName(AFormOrDockPanel)]);
       DebugWriteChildAnchors(AFormOrDockPanel,true,true);
       if AFormOrDockPanel is TAnchorDockPanel then begin
-        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),{false}true);
+        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),true,false);
         //LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         //TAnchorDockPanel(AFormOrDockPanel).SaveLayout(LayoutTree,LayoutNode);
       end else if AFormOrDockPanel is TAnchorDockHostSite then begin
@@ -3132,12 +3344,12 @@
         LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         Site.SaveLayout(LayoutTree,LayoutNode);
       end else if IsCustomSite(AFormOrDockPanel) then begin
-        SaveFormOrDockPanel(AFormOrDockPanel,true);
+        SaveFormOrDockPanel(AFormOrDockPanel,true,false);
       end else
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    LayoutTree.Root.Simplify(VisibleControls);
+    LayoutTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;
@@ -3157,7 +3369,7 @@
     (AControl as TAnchorDockPanel).SaveLayout(LayoutTree,LayoutTree.Root);
   end else if IsCustomSite(AControl) then begin
     LayoutTree.Root.NodeType:=adltnCustomSite;
-    LayoutTree.Root.Assign(AControl);
+    LayoutTree.Root.Assign(AControl,false,false);
     // can have one normal dock site
     Site:=TAnchorDockManager(AControl.DockManager).GetChildSite;
     if Site<>nil then begin
@@ -3252,7 +3464,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -3262,6 +3474,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -3323,6 +3536,7 @@
   HeaderFlatten                    := Settings.HeaderFlatten;
   HeaderFilled                     := Settings.HeaderFilled;
   HeaderHighlightFocused           := Settings.HeaderHighlightFocused;
+  DockSitesCanBeMinimized          := Settings.DockSitesCanBeMinimized;
 end;
 
 procedure TAnchorDockMaster.SaveSettings(Settings: TAnchorDockSettings);
@@ -3343,6 +3557,7 @@
   Settings.HeaderFlatten:=HeaderFlatten;
   Settings.HeaderFilled:=HeaderFilled;
   Settings.HeaderHighlightFocused:=HeaderHighlightFocused;
+  Settings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized;
 end;
 
 function TAnchorDockMaster.SettingsAreEqual(Settings: TAnchorDockSettings
@@ -3436,8 +3651,11 @@
   if fUpdateCount<=0 then
     RaiseGDBException('');
   dec(fUpdateCount);
-  if fUpdateCount=0 then
+  if fUpdateCount=0 then begin
     SimplifyPendingLayouts;
+    UpdateHeaders;
+    InvalidateHeaders;
+  end;
 end;
 
 function TAnchorDockMaster.IsReleasing(AControl: TControl): Boolean;
@@ -3664,6 +3882,24 @@
   LUIncreaseChangeStamp64(FOptionsChangeStamp);
 end;
 
+procedure TAnchorDockMaster.UpdateHeaders;
+var
+  i: Integer;
+  AControl: TControl;
+  AHostSite: TAnchorDockHostSite;
+begin
+    for i:=0 to ControlCount-1 do begin
+      AControl:=Controls[i];
+      if not DockedControlIsVisible(AControl) then continue;
+      while Assigned(AControl) do
+      begin
+        if AControl is TAnchorDockHostSite then
+          TAnchorDockHostSite(AControl).UpdateHeaderShowing;
+        AControl:=AControl.parent;
+      end;
+    end;
+end;
+
 { TAnchorDockHostSite }
 
 procedure TAnchorDockHostSite.SetHeaderSide(const AValue: TAnchorKind);
@@ -3680,6 +3916,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -4119,6 +4356,8 @@
 end;
 
 procedure TAnchorDockHostSite.FreePages;
+var
+  i:Integer;
 begin
   FreeAndNil(FPages);
 end;
@@ -4233,6 +4472,14 @@
         akRight: NewBounds.Right:=AControl.Left+AControl.Width;
         akBottom: NewBounds.Bottom:=AControl.Top+AControl.Height;
         end;
+        if (sibling is TAnchorDockHostSite) then
+        if (sibling as TAnchorDockHostSite).FMinimized then begin
+          (sibling as TAnchorDockHostSite).FMinimized:=false;
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Parent:=(sibling as TAnchorDockHostSite);
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Visible:=True;
+          (sibling as TAnchorDockHostSite).FMinimizedControl:=nil;
+          (sibling as TAnchorDockHostSite).UpdateHeaderAlign;
+        end;
         Sibling.BoundsRect:=NewBounds;
       end;
     end;
@@ -4306,6 +4553,13 @@
       FSiteType:=adhstOneControl;
       OnlySiteLeft.Align:=alClient;
       Header.Parent:=Self;
+      if OnlySiteLeft.FMinimized then begin
+        OnlySiteLeft.FMinimized:=false;
+        OnlySiteLeft.FMinimizedControl.Parent:=OnlySiteLeft;
+        OnlySiteLeft.FMinimizedControl.Visible:=True;
+        OnlySiteLeft.FMinimizedControl:=nil;
+        UpdateHeaderAlign;
+      end;
       UpdateHeaderAlign;
 
       //debugln(['TAnchorDockHostSite.RemoveControlFromLayout.ConvertToOneControlType AFTER CONVERT "',Caption,'" to onecontrol OnlySiteLeft="',OnlySiteLeft.Caption,'"']);
@@ -4465,7 +4719,7 @@
     debugln(['TAnchorDockHostSite.Simplify ',DbgSName(Self),' ',DbgSName(AControl)]);
     if AControl is TAnchorDockHostSite then
       SimplifyOneControl
-    else if (AControl=nil) or (csDestroying in AControl.ComponentState) then
+    else if ((AControl=nil) or (csDestroying in AControl.ComponentState)) then
       DockMaster.NeedFree(Self);
   end;
 end;
@@ -4577,7 +4831,8 @@
     Result:=Controls[i];
     if Result.Owner<>Self then exit;
   end;
-  Result:=nil;
+  result:=FMinimizedControl;
+  //Result:=nil;
 end;
 
 function TAnchorDockHostSite.GetSiteCount: integer;
@@ -5165,6 +5420,119 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+function TAnchorDockHostSite.CanBeMinimized(out Splitter: TAnchorDockSplitter;
+                                            out SplitterAnchorKind:TAnchorKind):boolean;
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+begin
+  result:=false;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) then
+      result:=true;
+  end
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+begin
+  //Application.QueueAsyncCall(@AsyncMinimizeSite,0);
+  AsyncMinimizeSite(0);
+end;
+
+procedure TAnchorDockHostSite.AsyncMinimizeSite(Data: PtrInt);
+var
+  AControl: TControl;
+  //OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  fMinimization:=true;
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  if FMinimized then
+    AControl:=FMinimizedControl
+  else
+    AControl:=GetOneControl;
+  if CanBeMinimized(Splitter,SplitterAnchorKind) or FMinimized then begin
+    FMinimized:=not FMinimized;
+    if FMinimized then begin
+      FMinimizedControl:=AControl;
+      AControl.Visible:=False;
+      AControl.Parent:=nil;
+      //self.DoDockOver(); OnDockOver;
+    end else begin
+      AControl.Parent:=self;
+      AControl.Visible:=True;
+      FMinimizedControl:=nil;
+    end;
+    Splitter.Enabled:=AControl.Visible;
+    UpdateHeaderAlign;
+    dockmaster.UpdateHeaders;
+    dockmaster.InvalidateHeaders;
+    Splitter.SetBoundsPercentually;
+  end;
+  fMinimization:=false;
+end;
+
+procedure TAnchorDockHostSite.ShowMinimizedControl;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  SpliterRect,OverlappingFormRect:TRect;
+begin
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    SpliterRect:=Splitter.GetSpliterBoundsWithUnminimizedDockSites;
+    OverlappingFormRect:=BoundsRect;
+    case SplitterAnchorKind of
+         akTop:OverlappingFormRect.Top:=SpliterRect.Bottom;
+        akLeft:OverlappingFormRect.Left:=SpliterRect.Right;
+       akRight:OverlappingFormRect.Right:=SpliterRect.Left;
+      akBottom:OverlappingFormRect.Bottom:=SpliterRect.Top;
+    end;
+    DockMaster.FOverlappingForm:=TAnchorDockOverlappingForm.CreateNew(self);
+    DockMaster.FOverlappingForm.BoundsRect:=OverlappingFormRect;
+    DockMaster.FOverlappingForm.Parent:=GetParentFormOrDockPanel(self,false);
+    DockMaster.FOverlappingForm.AnchorDockHostSite:=self;
+    header.Parent:=DockMaster.FOverlappingForm;
+    FMinimizedControl.Parent:=DockMaster.FOverlappingForm.Panel;
+    FMinimizedControl.Show;
+    DockMaster.ShowOverlappingForm;
+  end;
+end;
+
+procedure TAnchorDockHostSite.HideMinimizedControl;
+begin
+   FMinimizedControl.Hide;
+   header.Parent:=self;
+   header.UpdateHeaderControls;
+   FMinimizedControl.Parent:=nil;
+   FreeAndNil(DockMaster.FOverlappingForm);
+end;
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5281,21 +5649,24 @@
 begin
   if csDestroying in ComponentState then exit;
   NewCaption:='';
-  for i:=0 to ControlCount-1 do begin
-    Child:=Controls[i];
-    if Child=Exclude then continue;
-    if (Child.HostDockSite=Self) or (Child is TAnchorDockHostSite)
-    or (Child is TAnchorDockPageControl) then begin
-      if NewCaption<>'' then
-        NewCaption:=NewCaption+',';
-      NewCaption:=NewCaption+Child.Caption;
+  if FMinimized then
+    NewCaption:=FMinimizedControl.Caption
+  else
+    for i:=0 to ControlCount-1 do begin
+      Child:=Controls[i];
+      if Child=Exclude then continue;
+      if (Child.HostDockSite=Self) or (Child is TAnchorDockHostSite)
+      or (Child is TAnchorDockPageControl) then begin
+        if NewCaption<>'' then
+          NewCaption:=NewCaption+',';
+        NewCaption:=NewCaption+Child.Caption;
+      end;
     end;
-  end;
   OldCaption:=Caption;
   Caption:=NewCaption;
   //debugln(['TAnchorDockHostSite.UpdateDockCaption Caption="',Caption,'" NewCaption="',NewCaption,'" HasParent=',Parent<>nil,' ',DbgSName(Header)]);
-  if ((Parent=nil) and DockMaster.HideHeaderCaptionFloatingControl)
-  or (not DockMaster.ShowHeaderCaption) then
+  if {((Parent=nil) and DockMaster.HideHeaderCaptionFloatingControl)
+  or (not DockMaster.ShowHeaderCaption)}false then
     Header.Caption:=''
   else
     Header.Caption:=Caption;
@@ -5306,9 +5677,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm));
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5339,7 +5709,8 @@
   end;
 
   CanDock:=(Client is TAnchorDockHostSite)
-           and not DockMaster.AutoFreedIfControlIsRemoved(Self,Client);
+           and not DockMaster.AutoFreedIfControlIsRemoved(Self,Client)
+           and not FMinimized;
   //debugln(['TAnchorDockHostSite.GetSiteInfo ',DbgSName(Self),' ',dbgs(BoundsRect),' ',Caption,' CanDock=',CanDock,' PtIn=',PtInRect(InfluenceRect,MousePos)]);
 
   if Assigned(OnGetSiteInfo) then
@@ -5362,9 +5733,33 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+const
+OppositeAlign: array[TAnchorKind] of TAlign = (
+  alBottom, // akTop,
+  alRight,  // akLeft,
+  alLeft,   // akRight,
+  alTop     // akBottom
+  );
+OppositeAnchorKindAlign: array[TAnchorKind] of TADLHeaderPosition = (
+  adlhpBottom, // akTop,
+  adlhpRight,  // akLeft,
+  adlhpLeft,   // akRight,
+  adlhpTop     // akBottom
+  );
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      NeededHeaderPosition:=OppositeAnchorKindAlign[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5388,10 +5783,16 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderShowing;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  if HeaderNeedsShowing then
-    Header.Parent:=Self
+  if HeaderNeedsShowing then begin
+    Header.Parent:=Self;
+    Header.MinimizeButton.Visible:=(DockMaster.DockSitesCanBeMinimized and CanBeMinimized(Splitter,SplitterAnchorKind))or FMinimized;
+    Header.MinimizeButton.Parent:=Header;
+  end
   else
     Header.Parent:=nil;
 end;
@@ -5432,7 +5833,7 @@
   if (SiteType=adhstOneControl) and (OneControl<>nil)
   and (not (OneControl is TAnchorDockHostSite)) then begin
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.Name:=OneControl.Name;
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if (SiteType in [adhstLayout,adhstOneControl]) then begin
@@ -5450,7 +5851,7 @@
         Splitter.SaveLayout(ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if SiteType=adhstPages then begin
     LayoutNode.NodeType:=adltnPages;
@@ -5461,7 +5862,7 @@
         Site.SaveLayout(LayoutTree,ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else
     LayoutNode.NodeType:=adltnNone;
@@ -5476,6 +5877,9 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
+  fMinimization:=false;
+  FMinimizedControl:=Nil;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5490,13 +5894,13 @@
 end;
 
 destructor TAnchorDockHostSite.Destroy;
-//var i: Integer;
+var i: Integer;
 begin
-  //debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
-  {for i:=0 to ComponentCount-1 do
+  debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
+  for i:=0 to ComponentCount-1 do
     debugln(['TAnchorDockHostSite.Destroy Component ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   for i:=0 to ControlCount-1 do
-    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);}
+    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);
   FreePages;
   inherited Destroy;
 end;
@@ -5562,13 +5966,34 @@
 end;
 
 procedure TAnchorDockHeader.CloseButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
 begin
-  if Parent is TAnchorDockHostSite then begin
-    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(Parent),true);
-    TAnchorDockHostSite(Parent).CloseSite;
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
   end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(HeaderParent),true);
+    HeaderParent.CloseSite;
+  end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
+begin
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
+  end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    HeaderParent.MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5635,11 +6060,18 @@
 
   if CloseButton.IsControlVisible and (CloseButton.Parent=Self) then begin
     if Align in [alLeft,alRight] then
-      r.Top:=CloseButton.Top+CloseButton.Height+1
+      r.Top:=CloseButton.Top+CloseButton.Height+ButtonBorderSpacingAround
     else
-      r.Right:=CloseButton.Left-1;
+      r.Right:=CloseButton.Left-ButtonBorderSpacingAround;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+ButtonBorderSpacingAround
+    else
+      r.Right:=MinimizeButton.Left-ButtonBorderSpacingAround;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,26 +6160,127 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
   X, Y: Integer);
+var
+  SiteMinimized:Boolean;
 begin
   inherited MouseDown(Button, Shift, X, Y);
-  if (Button=mbLeft) and DockMaster.AllowDragging then
-    DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
+  SiteMinimized:=False;
+  fUseTimer:=false;
+  StopMouseNoMoveTimer;
+  if Parent is TAnchorDockHostSite then
+    SiteMinimized:=(Parent as TAnchorDockHostSite).FMinimized;
+  if SiteMinimized then begin
+    DoMouseNoMoveTimer(nil);
+  end else
+    begin
+      if parent<>nil then
+        if DockMaster.FOverlappingForm<>nil then
+          //if parent=DockMaster.FOverlappingForm.Panel then
+            DockMaster.HideOverlappingForm(nil);
+      if (Button=mbLeft) and (DockMaster.AllowDragging) and (DockMaster.FOverlappingForm=nil) then
+        DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
+    end;
 end;
 
+procedure  TAnchorDockHeader.MouseMove(Shift: TShiftState; X,Y: Integer);
+begin
+  inherited MouseMove(Shift, X, Y);
+  if parent<>nil then
+    if parent is TAnchorDockHostSite then
+      if (parent as TAnchorDockHostSite).FMinimized then
+        if DockMaster.FOverlappingForm=nil then
+          if FMouseTimeStartX=EmptyMouseTimeStartX then
+            StartMouseNoMoveTimer(X, Y)
+          else begin
+            if (abs(FMouseTimeStartX-X)>MouseNoMoveDelta)or(abs(FMouseTimeStartY-Y)>MouseNoMoveDelta)then
+            StopMouseNoMoveTimer;
+          end;
+  if (parent is TAnchorDockHostSite)and(DockMaster.FOverlappingForm=nil)then
+    fUseTimer:=true;
+end;
+
+procedure TAnchorDockHeader.MouseLeave;
+begin
+  inherited;
+  StopMouseNoMoveTimer;
+end;
+
+procedure TAnchorDockHeader.StartMouseNoMoveTimer(X, Y: Integer);
+begin
+  if fUseTimer then begin
+    if DockTimer.Enabled then DockTimer.Enabled:=false;
+    DockTimer.Interval:=MouseNoMoveTime;
+    DockTimer.OnTimer:=@DoMouseNoMoveTimer;
+    DockTimer.Enabled:=true;
+  end;
+end;
+
+procedure TAnchorDockHeader.StopMouseNoMoveTimer;
+begin
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  DockTimer.OnTimer:=nil;
+  DockTimer.Enabled:=false;
+end;
+
+procedure TAnchorDockHeader.DoMouseNoMoveTimer(Sender: TObject);
+begin
+  StopMouseNoMoveTimer;
+  //if fUseTimer then
+    if parent<>nil then
+      if parent is TAnchorDockHostSite then
+        if (parent as TAnchorDockHostSite).FMinimized then
+          (parent as TAnchorDockHostSite).ShowMinimizedControl;
+end;
+
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
-      CloseButton.Align:=alTop;
+    if CloseButton<>nil then begin
+      //MinimizeButton.Align:=alTop;
+      //CloseButton.Align:=alTop;
+      CloseButton.AnchorSide[akRight].Side := asrCenter;
+      CloseButton.AnchorSide[akRight].Control := self;
+      CloseButton.AnchorSide[akTop].Side := asrTop;
+      CloseButton.AnchorSide[akTop].Control := self;
+      CloseButton.Anchors := CloseButton.Anchors + [akTop] + [akRight];
+
+      MinimizeButton.AnchorSide[akRight].Side := asrCenter;
+      MinimizeButton.AnchorSide[akRight].Control := CloseButton;
+      MinimizeButton.AnchorSide[akTop].Side := asrBottom;
+      MinimizeButton.AnchorSide[akTop].Control := CloseButton;
+      MinimizeButton.Anchors := MinimizeButton.Anchors + [akTop] + [akRight];
+    end;
   end else begin
-    if CloseButton<>nil then
-      CloseButton.Align:=alRight;
+    if CloseButton<>nil then begin
+      //MinimizeButton.Align:=alRight;
+      //CloseButton.Align:=alRight;
+      CloseButton.AnchorSide[akRight].Side := asrRight;
+      CloseButton.AnchorSide[akRight].Control := self;
+      CloseButton.AnchorSide[akTop].Side := asrCenter;
+      CloseButton.AnchorSide[akTop].Control := self;
+      CloseButton.Anchors := CloseButton.Anchors - [akLeft] + [akRight];
+
+      MinimizeButton.AnchorSide[akRight].Side := asrLeft;
+      MinimizeButton.AnchorSide[akRight].Control := CloseButton;
+      MinimizeButton.AnchorSide[akTop].Side := asrCenter;
+      MinimizeButton.AnchorSide[akTop].Control := CloseButton;
+      MinimizeButton.Anchors := MinimizeButton.Anchors - [akLeft] + [akRight];
+    end;
   end;
+  CloseButton.BorderSpacing.Around:=ButtonBorderSpacingAround;
+  MinimizeButton.BorderSpacing.Around:=ButtonBorderSpacingAround;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
 
@@ -5787,9 +6320,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,11 +6332,23 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
   PopupMenu:=DockMaster.GetPopupMenu;
   fFocused:=false;
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  fUseTimer:=true;
 end;
 
 { TAnchorDockCloseButton }
@@ -5830,6 +6375,31 @@
   Result := ThemeServices.GetElementDetails(WindowPart);
 end;
 
+procedure SizeCorrector(var current,recomend:integer);
+begin
+  if recomend<0 then begin
+    if current>0 then
+      recomend:=current
+    else
+      current:=HardcodedButtonSize;
+  end else begin
+      if current>recomend then
+        current:=recomend
+      else begin
+        if current>0 then
+         recomend:=current
+        else
+         current:=recomend;
+      end;
+  end;
+end;
+
+procedure ButtonSizeCorrector(var w,h:integer);
+begin
+  SizeCorrector(w,PreferredButtonWidth);
+  SizeCorrector(h,PreferredButtonHeight);
+end;
+
 procedure TAnchorDockCloseButton.CalculatePreferredSize(var PreferredWidth,
   PreferredHeight: integer; WithThemeSpace: Boolean);
 begin
@@ -5837,6 +6407,7 @@
   begin
     PreferredWidth:=cx;
     PreferredHeight:=cy;
+    ButtonSizeCorrector(PreferredWidth,PreferredHeight);
     {$IF defined(LCLGtk2) or defined(Carbon)}
     inc(PreferredWidth,2);
     inc(PreferredHeight,2);
@@ -5844,6 +6415,45 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMinButtonNormal;
+    if not IsEnabled then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonDisabled{$ELSE}twMinButtonDisabled{$ENDIF}
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonPushed{$ELSE}twMinButtonPushed{$ENDIF}
+    else
+    if FState = bsHot then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonHot{$ELSE}twMinButtonHot{$ENDIF}
+    else
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF};
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails({$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF})) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    ButtonSizeCorrector(PreferredWidth,PreferredHeight);
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6213,6 +6823,9 @@
   ClientRectChanged:=(WidthDiff<>0) or (HeightDiff<>0);
   if ClientRectChanged or PreferredSiteSizeAsSiteMinimum then
     AlignChilds;
+  if ClientRectChanged then
+    if DockMaster.FOverlappingForm<>nil then
+      DockMaster.HideOverlappingForm(nil);
 end;
 
 procedure TAnchorDockManager.SaveToStream(Stream: TStream);
@@ -6234,6 +6847,27 @@
     BestDistance:=CurDistance;
   end;
 
+  procedure UnMinimizeSitesAt;
+  var
+    i:integer;
+    Site: TAnchorDockHostSite;
+    ARect:trect;
+  begin
+    for i:=0 to DockMaster.ComponentCount-1 do begin
+      Site:=TAnchorDockHostSite(DockMaster.Components[i]);
+      if not (Site is TAnchorDockHostSite) then continue;
+      if not Site.Showing then continue;
+      if not Site.Enabled then continue;
+      if not Site.IsVisible then continue;
+      ARect.TopLeft:=Site.ClientToScreen(point(0,0));
+      ARect.BottomRight:=Site.ClientToScreen(point(Site.Width,Site.Height));
+      InflateRect(ARect,DockMaster.DragTreshold+10,DockMaster.DragTreshold+10);
+      if PtInRect(ARect, ADockObject.DragPos) then
+      if Site.FMinimized then
+        Application.QueueAsyncCall(@Site.AsyncMinimizeSite,0);
+    end;
+  end;
+
 var
   p: TPoint;
   LastTabRect: TRect;
@@ -6245,6 +6879,8 @@
     exit(false);
   end;
 
+  UnMinimizeSitesAt;
+
   p:=Site.ScreenToClient(ADockObject.DragPos);
   //debugln(['TAnchorDockManager.GetDockEdge ',dbgs(p),' ',dbgs(Site.BoundsRect),' ',DbgSName(Site)]);
   if (DockSite<>nil) and (DockSite.Pages<>nil) then begin
@@ -6505,32 +7141,58 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
@@ -6560,14 +7222,47 @@
   end;
 end;
 
+function TAnchorDockSplitter.GetSpliterBoundsWithUnminimizedDockSites:TRect;
+var
+  NewLeft, NewTop: Integer;
+begin
+  if ResizeAnchor in [akLeft,akRight] then
+  begin
+    if DockParentClientSize.cx> 0 then
+    begin
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+      else
+        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+      NewTop := Top;
+    end;
+  end else
+  begin
+    if DockParentClientSize.cy> 0 then
+    begin
+      NewLeft := Left;
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewTop := Round(FPercentPosition*Parent.ClientHeight)
+      else
+        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    end;
+  end;
+  result:=Rect(NewLeft,NewTop,NewLeft+Width,NewTop+Height);
+end;
+
 procedure TAnchorDockSplitter.SaveLayout(
   LayoutNode: TAnchorDockLayoutTreeNode);
+var
+  NewLeft, NewTop: Integer;
 begin
   if ResizeAnchor in [akLeft,akRight] then
     LayoutNode.NodeType:=adltnSplitterVertical
   else
     LayoutNode.NodeType:=adltnSplitterHorizontal;
-  LayoutNode.Assign(Self);
+  LayoutNode.Assign(Self,false,false);
+  if not Enabled then begin
+    LayoutNode.BoundsRect:=GetSpliterBoundsWithUnminimizedDockSites;
+  end
 end;
 
 function TAnchorDockSplitter.HasOnlyOneSibling(Side: TAnchorKind; MinPos,
@@ -6645,7 +7340,7 @@
 begin
   inherited MouseDown(Button, Shift, X, Y);
   ATabIndex := IndexOfPageAt(X, Y);
-  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) then
+  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) and (DockMaster.FOverlappingForm=nil) then
   begin
     APage:=Page[ATabIndex];
     if (APage.ControlCount>0) and (APage.Controls[0] is TAnchorDockHostSite) then
@@ -6782,6 +7477,20 @@
   PopupMenu:=DockMaster.GetPopupMenu;
 end;
 
+{ TAnchorDockOverlappingForm }
+
+constructor TAnchorDockOverlappingForm.CreateNew(AOwner: TComponent; Num: Integer = 0);
+begin
+  inherited;
+  BorderStyle:=bsNone;
+  AnchorDockHostSite:=nil;
+  Panel:=TPanel.Create(self);
+  Panel.BorderStyle:=bsSingle;
+  Panel.Align:=alClient;
+  Panel.Parent:=self;
+  Panel.Visible:=true;
+end;
+
 { TAnchorDockPage }
 
 procedure TAnchorDockPage.UpdateDockCaption(Exclude: TControl);
@@ -6835,9 +7544,11 @@
 
 initialization
   DockMaster:=TAnchorDockMaster.Create(nil);
+  DockTimer:=TTimer.Create(nil);
 
 finalization
   FreeAndNil(DockMaster);
+  FreeAndNil(DockTimer);
 
 end.
 
Index: components/anchordocking/anchordockoptionsdlg.lfm
===================================================================
--- components/anchordocking/anchordockoptionsdlg.lfm	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.lfm	(working copy)
@@ -1,11 +1,13 @@
 object AnchorDockOptionsFrame: TAnchorDockOptionsFrame
   Left = 0
-  Height = 482
+  Height = 567
   Top = 0
-  Width = 416
-  ClientHeight = 482
-  ClientWidth = 416
+  Width = 490
+  ClientHeight = 567
+  ClientWidth = 490
+  DesignTimePPI = 113
   OnClick = FrameClick
+  ParentFont = False
   TabOrder = 0
   DesignLeft = 513
   DesignTop = 189
@@ -12,14 +14,15 @@
   object DragThresholdLabel: TLabel
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
-    Left = 10
-    Height = 13
-    Top = 10
-    Width = 111
-    BorderSpacing.Left = 10
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 12
+    Width = 122
+    BorderSpacing.Left = 12
+    BorderSpacing.Top = 12
     Caption = 'DragThresholdLabel'
     ParentColor = False
+    ParentFont = False
   end
   object DragThresholdTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdLabel
@@ -27,15 +30,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 23
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 31
+    Width = 466
     Max = 20
     OnChange = DragThresholdTrackBarChange
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Right = 10
+    BorderSpacing.Right = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 1
@@ -46,12 +50,13 @@
     AnchorSideTop.Control = DragThresholdLabel
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
-    Left = 127
-    Height = 23
-    Top = 5
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 141
+    Height = 27
+    Top = 8
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 20
+    ParentFont = False
     TabOrder = 0
     Visible = False
   end
@@ -59,13 +64,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = DragThresholdTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 79
-    Width = 103
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 97
+    Width = 112
+    BorderSpacing.Top = 12
     Caption = 'SplitterWidthLabel'
     ParentColor = False
+    ParentFont = False
   end
   object SplitterWidthTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdTrackBar
@@ -73,14 +79,15 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 92
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 116
+    Width = 466
     Min = 1
     OnChange = SplitterWidthTrackBarChange
     Position = 1
     Anchors = [akTop, akLeft, akRight]
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 3
@@ -89,12 +96,13 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = SplitterWidthTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 142
-    Width = 160
-    BorderSpacing.Top = 4
+    Left = 12
+    Height = 23
+    Top = 175
+    Width = 169
+    BorderSpacing.Top = 5
     Caption = 'ScaleOnResizeCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 4
@@ -103,12 +111,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 166
-    Width = 149
+    Left = 12
+    Height = 23
+    Top = 198
+    Width = 160
     Caption = 'ShowHeaderCheckBox'
     OnChange = ShowHeaderCheckBoxChange
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 5
@@ -117,12 +126,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ShowHeaderCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 190
-    Width = 191
-    BorderSpacing.Left = 15
+    Left = 30
+    Height = 23
+    Top = 221
+    Width = 208
+    BorderSpacing.Left = 18
     Caption = 'ShowHeaderCaptionCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 6
@@ -131,11 +141,12 @@
     AnchorSideLeft.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 214
-    Width = 249
+    Left = 30
+    Height = 23
+    Top = 244
+    Width = 272
     Caption = 'HideHeaderCaptionForFloatingCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 7
@@ -147,15 +158,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 122
+    Left = 136
     Height = 27
-    Top = 286
-    Width = 284
+    Top = 313
+    Width = 342
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 6
-    BorderSpacing.Right = 10
-    ItemHeight = 0
+    BorderSpacing.Left = 7
+    BorderSpacing.Right = 12
+    ItemHeight = 19
     OnDrawItem = HeaderStyleComboBoxDrawItem
+    ParentFont = False
     Style = csDropDownList
     TabOrder = 10
   end
@@ -163,23 +175,25 @@
     AnchorSideLeft.Control = ShowHeaderCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrCenter
-    Left = 20
-    Height = 13
-    Top = 293
-    Width = 96
-    BorderSpacing.Left = 10
+    Left = 24
+    Height = 19
+    Top = 317
+    Width = 105
+    BorderSpacing.Left = 12
     Caption = 'HeaderStyleLabel'
     ParentColor = False
+    ParentFont = False
   end
   object FlattenHeadersCheckBox: TCheckBox
     AnchorSideLeft.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 238
-    Width = 164
+    Left = 30
+    Height = 23
+    Top = 267
+    Width = 175
     Caption = 'FlattenHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 8
@@ -188,11 +202,12 @@
     AnchorSideLeft.Control = FlattenHeadersCheckBox
     AnchorSideTop.Control = FlattenHeadersCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 262
-    Width = 154
+    Left = 30
+    Height = 23
+    Top = 290
+    Width = 164
     Caption = 'FilledHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 9
@@ -201,11 +216,12 @@
     AnchorSideLeft.Control = FilledHeadersCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 313
-    Width = 175
+    Left = 30
+    Height = 23
+    Top = 340
+    Width = 189
     Caption = 'HighlightFocusedCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 11
@@ -215,13 +231,14 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = SplitterWidthLabel
     AnchorSideTop.Side = asrCenter
-    Left = 119
-    Height = 23
-    Top = 74
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 131
+    Height = 27
+    Top = 93
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 10
     MinValue = 1
+    ParentFont = False
     TabOrder = 2
     Value = 1
     Visible = False
@@ -228,15 +245,16 @@
   end
   object HeaderAlignTopLabel: TLabel
     AnchorSideLeft.Control = DragThresholdLabel
-    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Control = DockSitesCanBeMinimized
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 347
-    Width = 117
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 398
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignTopLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignTopTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -244,10 +262,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 360
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 417
+    Width = 466
     Frequency = 10
     Max = 150
     OnChange = HeaderAlignTopTrackBarChange
@@ -254,7 +272,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 13
@@ -264,12 +283,13 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignTopLabel
     AnchorSideTop.Side = asrCenter
-    Left = 133
-    Height = 23
-    Top = 342
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 394
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 150
+    ParentFont = False
     TabOrder = 12
     Visible = False
   end
@@ -277,13 +297,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = HeaderAlignTopTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 417
-    Width = 120
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 484
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignLeftLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignLeftTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -291,10 +312,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 430
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 503
+    Width = 466
     Frequency = 10
     Max = 200
     OnChange = HeaderAlignLeftTrackBarChange
@@ -301,7 +322,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 15
@@ -311,13 +333,28 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignLeftLabel
     AnchorSideTop.Side = asrCenter
-    Left = 136
-    Height = 23
-    Top = 412
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 480
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 200
+    ParentFont = False
     TabOrder = 14
     Visible = False
   end
+  object DockSitesCanBeMinimized: TCheckBox
+    AnchorSideLeft.Control = FilledHeadersCheckBox
+    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Side = asrBottom
+    Left = 30
+    Height = 23
+    Top = 363
+    Width = 185
+    Caption = 'DockSitesCanBeMinimized'
+    ParentFont = False
+    ParentShowHint = False
+    ShowHint = True
+    TabOrder = 16
+  end
 end
Index: components/anchordocking/anchordockoptionsdlg.pas
===================================================================
--- components/anchordocking/anchordockoptionsdlg.pas	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.pas	(working copy)
@@ -37,6 +37,7 @@
     HeaderStyleLabel: TLabel;
     HideHeaderCaptionForFloatingCheckBox: TCheckBox;
     HighlightFocusedCheckBox: TCheckBox;
+    DockSitesCanBeMinimized: TCheckBox;
     ScaleOnResizeCheckBox: TCheckBox;
     ShowHeaderCaptionCheckBox: TCheckBox;
     ShowHeaderCheckBox: TCheckBox;
@@ -202,7 +203,7 @@
 
       HeaderAlignTopSpinEdit.Visible:=true;
       HeaderAlignTopTrackBar.Visible:=false;
-      HeaderAlignTopSpinEdit.AnchorToNeighbour(akTop,6,HighlightFocusedCheckBox);
+      HeaderAlignTopSpinEdit.AnchorToNeighbour(akTop,6,DockSitesCanBeMinimized);
       HeaderAlignTopLabel.AnchorVerticalCenterTo(HeaderAlignTopSpinEdit);
       UpdateHeaderAlignTopLabel;
 
@@ -299,6 +300,7 @@
   HeaderStyleLabel.Enabled:=HasHeaders;
   HeaderStyleComboBox.Enabled:=HasHeaders;
   HighlightFocusedCheckBox.Enabled:=HasHeaders;
+  DockSitesCanBeMinimized.Enabled:=HasHeaders;
 end;
 
 constructor TAnchorDockOptionsFrame.Create(TheOwner: TComponent);
@@ -356,6 +358,7 @@
   TheSettings.HeaderFilled:=FilledHeadersCheckBox.Checked;
   TheSettings.HeaderStyle:=TADHeaderStyle(HeaderStyleComboBox.ItemIndex);
   TheSettings.HeaderHighlightFocused:=HighlightFocusedCheckBox.Checked;
+  TheSettings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized.Checked;
 end;
 
 procedure TAnchorDockOptionsFrame.LoadFromSettings(
@@ -429,6 +432,10 @@
   HighlightFocusedCheckBox.Checked:=TheSettings.HeaderHighlightFocused;
   HighlightFocusedCheckBox.Caption:=adrsHighlightFocused;
   HighlightFocusedCheckBox.Hint:=adrsHighlightFocusedHint;
+
+  DockSitesCanBeMinimized.Checked:=TheSettings.DockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Caption:=adrsDockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Hint:=adrsDockSitesCanBeMinimizedHint;
 end;
 
 end.
Index: components/anchordocking/anchordockpanel.pas
===================================================================
--- components/anchordocking/anchordockpanel.pas	(revision 59428)
+++ components/anchordocking/anchordockpanel.pas	(working copy)
@@ -55,7 +55,7 @@
   begin
 
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,false);
     LayoutNode.Name:={OneControl.}Name;
 
     TAnchorDockHostSite(OneControl).SaveLayout(LayoutTree,LayoutNode);
Index: components/anchordocking/anchordockstorage.pas
===================================================================
--- components/anchordocking/anchordockstorage.pas	(revision 59428)
+++ components/anchordocking/anchordockstorage.pas	(working copy)
@@ -64,6 +64,7 @@
     FTabPosition: TTabPosition;
     FWindowState: TWindowState;
     FControlLocation: TADLControlLocation;
+    FMinimized: Boolean;
     function GetAnchors(Site: TAnchorKind): string;
     function GetBottom: integer;
     function GetHeight: integer;
@@ -90,6 +91,7 @@
     procedure SetTop(const AValue: integer);
     procedure SetWidth(const AValue: integer);
     procedure SetWindowState(const AValue: TWindowState);
+    procedure SetMinimized(const AValue: boolean);
   public
     constructor Create;
     destructor Destroy; override;
@@ -96,7 +98,7 @@
     procedure Clear;
     function IsEqual(Node: TAnchorDockLayoutTreeNode): boolean;
     procedure Assign(Node: TAnchorDockLayoutTreeNode); overload;
-    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean=false); overload;
+    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean); overload;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
     procedure LoadFromConfig(Path: string; Config: TRttiXMLConfig); overload;
     procedure SaveToConfig(Config: TConfigStorage); overload;
@@ -106,7 +108,7 @@
     procedure CheckConsistency; virtual;
 
     // simplifying
-    procedure Simplify(ExistingNames: TStrings);
+    procedure Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
     procedure DeleteNode(ChildNode: TAnchorDockLayoutTreeNode);
     function FindNodeBoundSplitter(ChildNode: TAnchorDockLayoutTreeNode;
                                    Side: TAnchorKind): TAnchorDockLayoutTreeNode;
@@ -135,6 +137,7 @@
     property Monitor: integer read FMonitor write SetMonitor;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property TabPosition: TTabPosition read FTabPosition write SetTabPosition;
+    property Minimized: Boolean read FMinimized write SetMinimized;
     function Count: integer;
     function IsSplitter: boolean;
     function IsRootWindow: boolean;
@@ -988,6 +991,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockLayoutTreeNode.SetMinimized(const AValue: boolean);
+begin
+  if FMinimized=AValue then exit;
+  FMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockLayoutTreeNode.SetTop(const AValue: integer);
 begin
   if Top=AValue then exit;
@@ -1084,6 +1094,7 @@
   BoundSplitterPos:=Node.BoundSplitterPos;
   WorkAreaRect:=Node.WorkAreaRect;
   Monitor:=Node.Monitor;
+  Minimized:=Node.Minimized;
   for a:=low(TAnchorKind) to high(TAnchorKind) do
     Anchors[a]:=Node.Anchors[a];
   while Count>Node.Count do Nodes[Count-1].Free;
@@ -1098,9 +1109,10 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean=false);
+procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean);
 var
   AnchorControl: TControl;
+  ParentForm:TCustomForm;
   a: TAnchorKind;
 begin
   Name:=AControl.Name;
@@ -1109,12 +1121,18 @@
   else
     BoundsRect:=AControl.BoundsRect;
   Align:=AControl.Align;
+  Minimized:=AMinimized;
   if (AControl.Parent=nil) and (AControl is TCustomForm) then begin
     WindowState:=TCustomForm(AControl).WindowState;
     Monitor:=TCustomForm(AControl).Monitor.MonitorNum;
     WorkAreaRect:=TCustomForm(AControl).Monitor.WorkareaRect;
-  end else
-    WindowState:=GetParentForm(AControl).WindowState;
+  end else begin
+    ParentForm:=GetParentForm(AControl);
+    if assigned(ParentForm) then
+      WindowState:=ParentForm.WindowState
+    else
+      WindowState:=wsNormal;
+  end;
   if AControl is TCustomTabControl then
     TabPosition:=TCustomTabControl(AControl).TabPosition
   else
@@ -1137,6 +1155,7 @@
   Clear;
   Name:=Config.GetValue('Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue('Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue('Minimized',false);
   Left:=Config.GetValue('Bounds/Left',0);
   Top:=Config.GetValue('Bounds/Top',0);
   Width:=Config.GetValue('Bounds/Width',0);
@@ -1171,6 +1190,7 @@
   Clear;
   Name:=Config.GetValue(Path+'Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue(Path+'Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue(Path+'Minimized',false);
   Left:=Config.GetValue(Path+'Bounds/Left',0);
   Top:=Config.GetValue(Path+'Bounds/Top',0);
   Width:=Config.GetValue(Path+'Bounds/Width',0);
@@ -1219,6 +1239,7 @@
                                           ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue('Header/TabPosition',ADLTabPostionNames[TabPosition],
                                              ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue('Minimized',Minimized,False);
   Config.SetDeleteValue('Monitor',Monitor,0);
   Config.SetDeleteValue('ChildCount',Count,0);
   for i:=1 to Count do begin
@@ -1252,6 +1273,7 @@
                                                ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue(Path+'Header/TabPosition',ADLTabPostionNames[TabPosition],
                                                   ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue(Path+'Minimized',Minimized,False);
   Config.SetDeleteValue(Path+'Monitor',Monitor,0);
   Config.SetDeleteValue(Path+'ChildCount',Count,0);
   for i:=1 to Count do
@@ -1397,7 +1419,7 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings);
+procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
 { Simplification rules:
    1. Control nodes without existing name are deleted.
    2. Empty layouts and pages are deleted
@@ -1406,16 +1428,18 @@
 var
   i: Integer;
   ChildNode: TAnchorDockLayoutTreeNode;
+  NodeMinimized:boolean;
 begin
   // simplify children
   i:=Count-1;
   while i>=0 do begin
     ChildNode:=Nodes[i];
-    ChildNode.Simplify(ExistingNames);
+    NodeMinimized:=ParentMinimized or ChildNode.Minimized;
+    ChildNode.Simplify(ExistingNames,NodeMinimized);
 
     if (ChildNode.NodeType=adltnControl) then begin
       // leaf node => check if there is a control
-      if (ChildNode.Name='') or (ExistingNames.IndexOf(ChildNode.Name)<0) then
+      if (ChildNode.Name='') or ((ExistingNames.IndexOf(ChildNode.Name)<0) and (not NodeMinimized)) then
         DeleteNode(ChildNode);
     end else if ChildNode.IsSplitter then begin
       // splitter
@@ -1424,7 +1448,7 @@
         ChildNode[0].Free;
     end else if ChildNode.NodeType=adltnCustomSite then begin
       // custom dock site
-    end else if ChildNode.Count=0 then begin
+    end else if (ChildNode.Count=0)and(not NodeMinimized) then begin
       // inner node without child => delete
       DeleteNode(ChildNode);
     end else if (ChildNode.Count=1)
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59428)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';
@@ -82,6 +83,8 @@
   adrsFilledHeadersHint = 'Fill headers of docked controls';
   adrsHighlightFocused = 'Highlight focused';
   adrsHighlightFocusedHint = 'Highlight header of focused docked control';
+  adrsDockSitesCanBeMinimized = 'Dock sites can be minimized';
+  adrsDockSitesCanBeMinimizedHint = 'Dock sites can be minimized';
 
 implementation
 
Index: components/anchordocking/design/anchordesktopoptions.pas
===================================================================
--- components/anchordocking/design/anchordesktopoptions.pas	(revision 59428)
+++ components/anchordocking/design/anchordesktopoptions.pas	(working copy)
@@ -272,7 +272,7 @@
         // custom dock site
         LayoutNode:=FTree.NewNode(FTree.Root);
         LayoutNode.NodeType:=adltnCustomSite;
-        LayoutNode.Assign(AForm);
+        LayoutNode.Assign(AForm,false,false);
         // can have one normal dock site
         Site:=TAnchorDockManager(AForm.DockManager).GetChildSite;
         if Site<>nil then begin
@@ -287,7 +287,7 @@
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    FTree.Root.Simplify(VisibleControls);
+    FTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;

<?xml version="1.0" encoding="utf-8"?>
<CONFIG>
  <MainConfig>
    <Nodes ChildCount="1">
      <Item1 Name="MainIDE" Type="CustomSite" ChildCount="1" WindowState="Maximized">
        <Bounds Top="-4" Left="-4" Width="1920" Height="1012">
          <WorkArea>
            <Rect Right="1920" Bottom="1036"/>
          </WorkArea>
        </Bounds>
        <Item1 Name="AnchorDockSite3" Type="Layout" ChildCount="7" WindowState="Maximized">
          <Bounds Top="80" Width="1920" Height="908" SplitterPos="75"/>
          <Anchors Align="Bottom"/>
          <Item1 Name="ObjectInspector" Type="Control" WindowState="Maximized">
            <Bounds Width="644" Height="908"/>
            <Anchors Right="AnchorDockSplitter2"/>
          </Item1>
          <Item2 Name="AnchorDockSplitter2" Type="SplitterVertical" WindowState="Maximized">
            <Bounds Left="644" Width="4" Height="908"/>
          </Item2>
          <Item3 Name="SourceEditor1" Type="Control" WindowState="Maximized">
            <Bounds Left="648" Width="779" Height="638"/>
            <Anchors Left="AnchorDockSplitter2" Right="AnchorDockSplitter4" Bottom="AnchorDockSplitter3"/>
          </Item3>
          <Item4 Name="AnchorDockSplitter3" Type="SplitterHorizontal" WindowState="Maximized">
            <Bounds Top="638" Left="648" Width="779" Height="4"/>
            <Anchors Left="AnchorDockSplitter2" Right="AnchorDockSplitter4"/>
          </Item4>
          <Item5 Name="AnchorDockSite4" Type="Pages" ChildCount="2" WindowState="Maximized">
            <Bounds Top="642" Left="648" Width="779" Height="266"/>
            <Anchors Top="AnchorDockSplitter3" Left="AnchorDockSplitter2" Right="AnchorDockSplitter4"/>
            <Item1 Name="FPDocEditor" Type="Control" WindowState="Maximized">
              <Bounds Width="320" Height="240"/>
              <Anchors Align="Client"/>
            </Item1>
            <Item2 Name="ProjectInspector" Type="Control" WindowState="Maximized">
              <Bounds Width="762" Height="240"/>
              <Anchors Align="Client"/>
            </Item2>
          </Item5>
          <Item6 Name="AnchorDockSplitter4" Type="SplitterVertical" WindowState="Maximized">
            <Bounds Left="1427" Width="4" Height="908"/>
          </Item6>
          <Item7 Name="Messages" Type="Control" WindowState="Maximized">
            <Bounds Left="1431" Width="489" Height="908"/>
            <Anchors Left="AnchorDockSplitter4"/>
          </Item7>
        </Item1>
      </Item1>
    </Nodes>
  </MainConfig>
  <Settings DockSitecCanBeMinimized="True"/>
</CONFIG>

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59428)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -109,6 +109,31 @@
 const ADAutoSizingReason = 'TAnchorDockMaster Delayed';
 {$ENDIF}
 
+const EmptyMouseTimeStartX=low(Integer);
+      MouseNoMoveDelta=5;
+      MouseNoMoveTime=500;
+      HideOverlappingFormByMouseLoseTime=500;
+      ButtonBorderSpacingAround=4;
+      OppositeAnchorKind2Align: array[TAnchorKind] of TAlign = (
+        alBottom, // akTop,
+        alRight,  // akLeft,
+        alLeft,   // akRight,
+        alTop     // akBottom
+        );
+      {AnchorKind2Align: array[TAnchorKind] of TAlign = (
+        alTop,  // akTop,
+        alLeft, // akLeft,
+        alRight,// akRight,
+        alBottom// akBottom
+        );}
+      OppositeAnchorKind2TADLHeaderPosition: array[TAnchorKind] of TADLHeaderPosition = (
+        adlhpBottom, // akTop,
+        adlhpRight,  // akLeft,
+        adlhpLeft,   // akRight,
+        adlhpTop     // akBottom
+        );
+
+
 type
   TAnchorDockHostSite = class;
 
@@ -123,6 +148,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +166,13 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
+    fUseTimer:Boolean;
+    FMouseTimeStartX,FMouseTimeStartY:Integer;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -147,6 +184,11 @@
           PreferredHeight: integer; WithThemeSpace: Boolean); override;
     procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X,
              Y: Integer); override;
+    procedure MouseMove(Shift: TShiftState; X,Y: Integer); override;
+    procedure MouseLeave;  override;
+    procedure StartMouseNoMoveTimer(X, Y: Integer);
+    procedure StopMouseNoMoveTimer;
+    procedure DoMouseNoMoveTimer(Sender: TObject);
     procedure UpdateHeaderControls;
     procedure SetAlign(Value: TAlign); override;
     procedure DoOnShowHint(HintInfo: PHintInfo); override;
@@ -154,6 +196,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -190,6 +233,7 @@
     procedure SetBoundsKeepDockBounds(ALeft, ATop, AWidth, AHeight: integer); // movement for scaling keeps the DockBounds
     function SideAnchoredControlCount(Side: TAnchorKind): integer;
     function HasAnchoredControls: boolean;
+    function GetSpliterBoundsWithUnminimizedDockSites:TRect;
     procedure SaveLayout(LayoutNode: TAnchorDockLayoutTreeNode);
     function HasOnlyOneSibling(Side: TAnchorKind; MinPos, MaxPos: integer): TControl;
     property DockRestoreBounds: TRect read FDockRestoreBounds write FDockRestoreBounds;
@@ -241,6 +285,14 @@
   end;
   TAnchorDockPageControlClass = class of TAnchorDockPageControl;
 
+
+  TAnchorDockOverlappingForm = class(TCustomForm)
+  public
+    AnchorDockHostSite:TAnchorDockHostSite;
+    Panel:TPanel;
+    constructor CreateNew(AOwner: TComponent; Num: Integer = 0); override;
+  end;
+
   { TAnchorDockHostSite
     This form is the dockhostsite for all controls.
     When docked together they build a tree structure with the docked controls
@@ -262,7 +314,10 @@
     FPages: TAnchorDockPageControl;
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
-    fUpdateLayout: integer;
+    fUpdateLayout: Integer;
+    FMinimized: Boolean;
+    fMinimization: Boolean;
+    FMinimizedControl: TControl;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +374,10 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
+    procedure AsyncMinimizeSite(Data: PtrInt);
+    procedure ShowMinimizedControl;
+    procedure HideMinimizedControl;
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -329,6 +388,7 @@
     procedure UpdateDockCaption(Exclude: TControl = nil); override;
     procedure UpdateHeaderAlign;
     procedure UpdateHeaderShowing;
+    function CanBeMinimized(out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
     procedure BeginUpdateLayout;
     procedure EndUpdateLayout;
     function UpdatingLayout: boolean;
@@ -337,6 +397,7 @@
     procedure SaveLayout(LayoutTree: TAnchorDockLayoutTree;
                          LayoutNode: TAnchorDockLayoutTreeNode);
     property DockRestoreBounds: TRect read FDockRestoreBounds write FDockRestoreBounds;
+    function GetDockEdge(const MousePos: TPoint): TAlign; override;
 
     property HeaderSide: TAnchorKind read FHeaderSide write SetHeaderSide;
     property Header: TAnchorDockHeader read FHeader;
@@ -431,6 +492,7 @@
     FShowHeader: boolean;
     FShowHeaderCaption: boolean;
     FSplitterWidth: integer;
+    FDockSitecCanBeMinimized: boolean;
     procedure SetAllowDragging(AValue: boolean);
     procedure SetDockOutsideMargin(AValue: integer);
     procedure SetDockParentMargin(AValue: integer);
@@ -448,6 +510,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitecCanBeMinimized(AValue: boolean);
   public
     property DragTreshold: integer read FDragTreshold write SetDragTreshold;
     property DockOutsideMargin: integer read FDockOutsideMargin write SetDockOutsideMargin;
@@ -466,6 +529,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused;
+    property DockSitesCanBeMinimized: boolean read FDockSitecCanBeMinimized write SetDockSitecCanBeMinimized;
     procedure IncreaseChangeStamp; inline;
     property ChangeStamp: integer read FChangeStamp;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
@@ -502,6 +566,7 @@
     FHeaderFlatten: boolean;
     FHeaderFilled: boolean;
     FHeaderHighlightFocused: boolean;
+    FDockSitesCanBeMinimized: boolean;
     FIdleConnected: Boolean;
     FManagerClass: TAnchorDockManagerClass;
     FOnCreateControl: TADCreateControlEvent;
@@ -531,6 +596,7 @@
     fPopupMenu: TPopupMenu;
     // Used by RestoreLayout:
     WorkArea, SrcWorkArea: TRect;
+    FOverlappingForm:TAnchorDockOverlappingForm;
 
     function GetControls(Index: integer): TControl;
     function GetLocalizedHeaderHint: string;
@@ -541,6 +607,9 @@
     function GetNodeSite(Node: TAnchorDockLayoutTreeNode): TAnchorDockHostSite;
     procedure MapTreeToControls(Tree: TAnchorDockLayoutTree);
     function RestoreLayout(Tree: TAnchorDockLayoutTree; Scale: boolean): boolean;
+    procedure SetMinimizedState(Tree: TAnchorDockLayoutTree);
+    procedure UpdateHeaders;
+    procedure SetnodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
     procedure EnableAllAutoSizing;
     procedure ClearLayoutProperties(AControl: TControl; NewAlign: TAlign = alClient);
     procedure PopupMenuPopup(Sender: TObject);
@@ -561,6 +630,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitesCanBeMinimized(AValue: boolean);
 
     procedure SetShowMenuItemShowHeader(AValue: boolean);
     procedure SetupSite(Site: TWinControl; ANode: TAnchorDockLayoutTreeNode;
@@ -584,8 +654,12 @@
     procedure SetHideHeaderCaptionFloatingControl(const AValue: boolean);
     procedure SetSplitterWidth(const AValue: integer);
     procedure OnIdle(Sender: TObject; var Done: Boolean);
+    procedure StartHideOverlappingTimer;
+    procedure StopHideOverlappingTimer;
     procedure AsyncSimplify({%H-}Data: PtrInt);
   public
+    procedure ShowOverlappingForm;
+    procedure HideOverlappingForm(Sender: TObject);
     constructor Create(AOwner: TComponent); override;
     destructor Destroy; override;
     function FullRestoreLayout(Tree: TAnchorDockLayoutTree; Scale: Boolean): Boolean;
@@ -680,6 +754,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten default true;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled default true;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused default false;
+    property DockSitesCanBeMinimized: boolean read FDockSitesCanBeMinimized write SetDockSitesCanBeMinimized default false;
 
     property SplitterWidth: integer read FSplitterWidth write SetSplitterWidth default 4;
     property ScaleOnResize: boolean read FScaleOnResize write SetScaleOnResize default true; // scale children when resizing a site
@@ -698,8 +773,14 @@
 
 var
   DockMaster: TAnchorDockMaster = nil;
+  DockTimer: TTimer = nil;
 
+  PreferredButtonWidth:integer=-1;
+  PreferredButtonHeight:integer=-1;
+
+
 const
+  HardcodedButtonSize:integer=13;
   ADHeaderStyleNames: array[TADHeaderStyle] of string = (
     'Frame3D',
     'Line',
@@ -970,6 +1051,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -1361,6 +1463,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockSettings.SetDockSitecCanBeMinimized(AValue: boolean);
+begin
+  if FDockSitecCanBeMinimized=AValue then Exit;
+  FDockSitecCanBeMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockSettings.Assign(Source: TAnchorDockSettings);
 begin
   FAllowDragging := Source.FAllowDragging;
@@ -1381,6 +1490,7 @@
   FShowHeaderCaption := Source.FShowHeaderCaption;
   FSplitterWidth := Source.FSplitterWidth;
   FHeaderHighlightFocused:=Source.FHeaderHighlightFocused;
+  FDockSitecCanBeMinimized:=Source.FDockSitecCanBeMinimized;
 end;
 
 procedure TAnchorDockSettings.IncreaseChangeStamp;
@@ -1407,6 +1517,7 @@
   HeaderFlatten:=Config.GetValue('HeaderFlatten',true);
   HeaderFilled:=Config.GetValue('HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue('HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue('DockSitecCanBeMinimized',False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1429,6 +1540,7 @@
   Config.SetDeleteValue(Path+'HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue(Path+'HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue(Path+'HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue(Path+'DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
 end;
 
 procedure TAnchorDockSettings.SaveToConfig(Config: TConfigStorage);
@@ -1450,6 +1562,7 @@
   Config.SetDeleteValue('HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue('HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue('HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue('DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1472,6 +1585,7 @@
       and (HeaderFlatten=Settings.HeaderFlatten)
       and (HeaderFilled=Settings.HeaderFilled)
       and (HeaderHighlightFocused=Settings.HeaderHighlightFocused)
+      and (DockSitesCanBeMinimized=Settings.DockSitesCanBeMinimized)
       ;
 end;
 
@@ -1494,6 +1608,7 @@
   HeaderFlatten:=Config.GetValue(Path+'HeaderFlatten',true);
   HeaderFilled:=Config.GetValue(Path+'HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue(Path+'HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue(Path+'DockSitecCanBeMinimized',False);
 end;
 
 { TAnchorDockMaster }
@@ -2021,6 +2136,8 @@
     aHostSite:=TAnchorDockHostSite(Site);
     aHostSite.Header.HeaderPosition:=ANode.HeaderPosition;
     aHostSite.DockRestoreBounds:=NewBounds;
+    //aHostSite.FMinimized:=ANode.Minimized;
+    //we update aHostSite.FMinimized in TAnchorDockMaster.SetMinimizedState
     if (ANode.NodeType<>adltnPages) and (aHostSite.Pages<>nil) then
       aHostSite.FreePages;
   end;
@@ -2040,6 +2157,25 @@
   fTreeNameToDocker[Node.Name]:=Result;
 end;
 
+procedure TAnchorDockMaster.SetNodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
+var
+  HostSite:TAnchorDockHostSite;
+  i:integer;
+begin
+  HostSite:=GetNodeSite(ANode);
+  if Assigned(HostSite) then
+    if HostSite.FMinimized<>ANode.Minimized then
+      Application.QueueAsyncCall(@HostSite.AsyncMinimizeSite,0);
+      //HostSite.MinimizeSite;
+  for i:=0 to ANode.Count-1 do
+    SetnodeMinimizedState(ANode.Nodes[i]);
+end;
+
+procedure TAnchorDockMaster.SetMinimizedState(Tree: TAnchorDockLayoutTree);
+begin
+  SetnodeMinimizedState(Tree.Root);
+end;
+
 function TAnchorDockMaster.RestoreLayout(Tree: TAnchorDockLayoutTree;
   Scale: boolean): boolean;
 
@@ -2193,7 +2329,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -2358,7 +2494,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -2368,6 +2504,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -2422,11 +2559,54 @@
   OptionsChanged;
 end;
 
+procedure TAnchorDockMaster.StartHideOverlappingTimer;
+begin
+  if not DockTimer.Enabled then begin
+    DockTimer.Interval:=HideOverlappingFormByMouseLoseTime;
+    DockTimer.OnTimer:=@HideOverlappingForm;
+    DockTimer.Enabled:=true;
+  end;
+end;
+
+procedure TAnchorDockMaster.StopHideOverlappingTimer;
+begin
+  DockTimer.Enabled:=False;
+  DockTimer.Interval:=0;
+  DockTimer.OnTimer:=nil;
+end;
+
+function IsParentControl(aParent, aControl: TControl): boolean;
+begin
+  while (aControl <> nil) and (aControl.Parent <> nil) do
+  begin
+    if (aControl=aParent) then
+      exit(true);
+    aControl := aControl.Parent;
+  end;
+  result:=aControl=aParent;
+end;
+
+
 procedure TAnchorDockMaster.OnIdle(Sender: TObject; var Done: Boolean);
+var
+  MousePos: TPoint;
+  Bounds:Trect;
 begin
   if Done then ;
-  IdleConnected:=false;
   Restoring:=false;
+  if FOverlappingForm=nil then
+    IdleConnected:=false
+  else begin
+    GetCursorPos(MousePos);
+    Bounds.TopLeft:=FOverlappingForm.ClientToScreen(point(0,0));
+    Bounds.BottomRight:=FOverlappingForm.ClientToScreen(point(FOverlappingForm.Width,FOverlappingForm.Height));
+    if not IsParentControl(FOverlappingForm, GetCaptureControl) then begin
+      if not PtInRect(Bounds,MousePos) then
+          StartHideOverlappingTimer
+        else
+          StopHideOverlappingTimer;
+    end;
+  end;
 end;
 
 procedure TAnchorDockMaster.AsyncSimplify(Data: PtrInt);
@@ -2514,6 +2694,18 @@
   InvalidateHeaders;
 end;
 
+procedure TAnchorDockMaster.SetDockSitesCanBeMinimized(AValue: boolean);
+var
+  i:integer;
+  Site: TAnchorDockHostSite;
+begin
+  if FDockSitesCanBeMinimized=AValue then Exit;
+  FDockSitesCanBeMinimized:=AValue;
+  UpdateHeaders;
+  InvalidateHeaders;
+  EnableAllAutoSizing;
+  OptionsChanged;
+end;
 procedure TAnchorDockMaster.SetScaleOnResize(AValue: boolean);
 begin
   if FScaleOnResize=AValue then Exit;
@@ -2598,6 +2790,9 @@
     if (Site.Header<>nil) then begin
       DisableControlAutoSizing(Site);
       Site.UpdateHeaderShowing;
+      if Site.fminimized then
+        if not AValue then
+          site.MinimizeSite;
     end;
   end;
   EnableAllAutoSizing;
@@ -2668,6 +2863,20 @@
     EnableAllAutoSizing;
 end;
 
+procedure TAnchorDockMaster.ShowOverlappingForm;
+begin
+  FOverlappingForm.Show;
+  IdleConnected:=true;
+end;
+
+procedure TAnchorDockMaster.HideOverlappingForm(Sender: TObject);
+begin
+  StopHideOverlappingTimer;
+  FOverlappingForm.Hide;
+  FOverlappingForm.AnchorDockHostSite.HideMinimizedControl;
+  IdleConnected:=false;
+end;
+
 constructor TAnchorDockMaster.Create(AOwner: TComponent);
 begin
   inherited Create(AOwner);
@@ -2698,14 +2907,14 @@
   FPageClass:=TAnchorDockPage;
   FRestoreLayouts:=TAnchorDockRestoreLayouts.Create;
   FHeaderHighlightFocused:=false;
+  FDockSitesCanBeMinimized:=false;
+  FOverlappingForm:=nil;
 end;
 
 destructor TAnchorDockMaster.Destroy;
 var
   AControl: TControl;
-  {$IFDEF VerboseAnchorDocking}
-  i: Integer;
-  {$ENDIF}
+  i, j: Integer;
 begin
   QueueSimplify:=false;
   FreeAndNil(FRestoreLayouts);
@@ -2727,6 +2936,12 @@
     debugln(['TAnchorDockMaster.Destroy ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   end;
   {$ENDIF}
+  for i:=0 to ComponentCount-1 do begin
+    for j:=0 to ComponentCount-1 do begin
+      if i<>j then
+        TControl(Components[i]).RemoveAllHandlersOfObject(TControl(Components[j]));
+  end;
+  end;
   inherited Destroy;
 end;
 
@@ -2914,6 +3129,7 @@
       raise Exception.Create('TAnchorDockMaster.MakeDockable '+Format(
         adrsNotSupportedHasParent, [DbgSName(AControl), DbgSName(AControl)]));
     end;
+    site.UpdateHeaderShowing;
     if (Site<>nil) and Show then
       MakeVisible(Site,BringToFront);
   finally
@@ -3018,7 +3234,8 @@
   i:=Screen.CustomFormCount-1;
   while i>=0 do begin
     AForm:=GetParentForm(Screen.CustomForms[i]);
-    AForm.Hide;
+    if Assigned(AForm)then
+      AForm.Hide;
     i:=Min(i,Screen.CustomFormCount)-1;
   end;
 
@@ -3062,8 +3279,11 @@
   end;
 end;
 
-function GetParentFormOrDockPanel(Control: TControl): TCustomForm;
+function GetParentFormOrDockPanel(Control: TControl; TopForm:Boolean=true): TCustomForm;
+var
+  oldControl: TControl;
 begin
+  oldControl:=Control;
   while (Control <> nil) and (Control.Parent <> nil) do
   begin
     if (Control is TAnchorDockPanel) then
@@ -3076,6 +3296,18 @@
     Result := TCustomForm(Control)
   else
     Result := nil;
+  if not TopForm then begin
+    if Control is TAnchorDockPanel then
+      exit;
+    Control:=oldControl;
+    while (Control <> nil) and (Control.Parent <> nil) do
+    begin
+      Control := Control.Parent;
+      if (Control is TCustomForm) then
+        Break;
+    end;
+    Result := TCustomForm(Control);
+  end;
 end;
 
 procedure TAnchorDockMaster.SaveMainLayoutToTree(LayoutTree: TAnchorDockLayoutTree);
@@ -3088,12 +3320,12 @@
   AFormOrDockPanel: TWinControl;
   VisibleControls: TStringList;
 
-  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean);
+  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean; AMinimized:boolean);
   begin
     // custom dock site
     LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
     LayoutNode.NodeType:=adltnCustomSite;
-    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel);
+    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel,AMinimized);
     // can have one normal dock site
     if SaveChildren then
     begin
@@ -3124,7 +3356,7 @@
       debugln(['TAnchorDockMaster.SaveMainLayoutToTree AForm=',DbgSName(AFormOrDockPanel)]);
       DebugWriteChildAnchors(AFormOrDockPanel,true,true);
       if AFormOrDockPanel is TAnchorDockPanel then begin
-        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),{false}true);
+        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),true,false);
         //LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         //TAnchorDockPanel(AFormOrDockPanel).SaveLayout(LayoutTree,LayoutNode);
       end else if AFormOrDockPanel is TAnchorDockHostSite then begin
@@ -3132,12 +3364,12 @@
         LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         Site.SaveLayout(LayoutTree,LayoutNode);
       end else if IsCustomSite(AFormOrDockPanel) then begin
-        SaveFormOrDockPanel(AFormOrDockPanel,true);
+        SaveFormOrDockPanel(AFormOrDockPanel,true,false);
       end else
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    LayoutTree.Root.Simplify(VisibleControls);
+    LayoutTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;
@@ -3157,7 +3389,7 @@
     (AControl as TAnchorDockPanel).SaveLayout(LayoutTree,LayoutTree.Root);
   end else if IsCustomSite(AControl) then begin
     LayoutTree.Root.NodeType:=adltnCustomSite;
-    LayoutTree.Root.Assign(AControl);
+    LayoutTree.Root.Assign(AControl,false,false);
     // can have one normal dock site
     Site:=TAnchorDockManager(AControl.DockManager).GetChildSite;
     if Site<>nil then begin
@@ -3252,7 +3484,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -3262,6 +3494,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -3323,6 +3556,7 @@
   HeaderFlatten                    := Settings.HeaderFlatten;
   HeaderFilled                     := Settings.HeaderFilled;
   HeaderHighlightFocused           := Settings.HeaderHighlightFocused;
+  DockSitesCanBeMinimized          := Settings.DockSitesCanBeMinimized;
 end;
 
 procedure TAnchorDockMaster.SaveSettings(Settings: TAnchorDockSettings);
@@ -3343,6 +3577,7 @@
   Settings.HeaderFlatten:=HeaderFlatten;
   Settings.HeaderFilled:=HeaderFilled;
   Settings.HeaderHighlightFocused:=HeaderHighlightFocused;
+  Settings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized;
 end;
 
 function TAnchorDockMaster.SettingsAreEqual(Settings: TAnchorDockSettings
@@ -3436,8 +3671,11 @@
   if fUpdateCount<=0 then
     RaiseGDBException('');
   dec(fUpdateCount);
-  if fUpdateCount=0 then
+  if fUpdateCount=0 then begin
     SimplifyPendingLayouts;
+    UpdateHeaders;
+    InvalidateHeaders;
+  end;
 end;
 
 function TAnchorDockMaster.IsReleasing(AControl: TControl): Boolean;
@@ -3664,6 +3902,24 @@
   LUIncreaseChangeStamp64(FOptionsChangeStamp);
 end;
 
+procedure TAnchorDockMaster.UpdateHeaders;
+var
+  i: Integer;
+  AControl: TControl;
+  AHostSite: TAnchorDockHostSite;
+begin
+    for i:=0 to ControlCount-1 do begin
+      AControl:=Controls[i];
+      if not DockedControlIsVisible(AControl) then continue;
+      while Assigned(AControl) do
+      begin
+        if AControl is TAnchorDockHostSite then
+          TAnchorDockHostSite(AControl).UpdateHeaderShowing;
+        AControl:=AControl.parent;
+      end;
+    end;
+end;
+
 { TAnchorDockHostSite }
 
 procedure TAnchorDockHostSite.SetHeaderSide(const AValue: TAnchorKind);
@@ -3680,6 +3936,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -4119,6 +4376,8 @@
 end;
 
 procedure TAnchorDockHostSite.FreePages;
+var
+  i:Integer;
 begin
   FreeAndNil(FPages);
 end;
@@ -4233,6 +4492,14 @@
         akRight: NewBounds.Right:=AControl.Left+AControl.Width;
         akBottom: NewBounds.Bottom:=AControl.Top+AControl.Height;
         end;
+        if (sibling is TAnchorDockHostSite) then
+        if (sibling as TAnchorDockHostSite).FMinimized then begin
+          (sibling as TAnchorDockHostSite).FMinimized:=false;
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Parent:=(sibling as TAnchorDockHostSite);
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Visible:=True;
+          (sibling as TAnchorDockHostSite).FMinimizedControl:=nil;
+          (sibling as TAnchorDockHostSite).UpdateHeaderAlign;
+        end;
         Sibling.BoundsRect:=NewBounds;
       end;
     end;
@@ -4306,6 +4573,13 @@
       FSiteType:=adhstOneControl;
       OnlySiteLeft.Align:=alClient;
       Header.Parent:=Self;
+      if OnlySiteLeft.FMinimized then begin
+        OnlySiteLeft.FMinimized:=false;
+        OnlySiteLeft.FMinimizedControl.Parent:=OnlySiteLeft;
+        OnlySiteLeft.FMinimizedControl.Visible:=True;
+        OnlySiteLeft.FMinimizedControl:=nil;
+        UpdateHeaderAlign;
+      end;
       UpdateHeaderAlign;
 
       //debugln(['TAnchorDockHostSite.RemoveControlFromLayout.ConvertToOneControlType AFTER CONVERT "',Caption,'" to onecontrol OnlySiteLeft="',OnlySiteLeft.Caption,'"']);
@@ -4465,7 +4739,7 @@
     debugln(['TAnchorDockHostSite.Simplify ',DbgSName(Self),' ',DbgSName(AControl)]);
     if AControl is TAnchorDockHostSite then
       SimplifyOneControl
-    else if (AControl=nil) or (csDestroying in AControl.ComponentState) then
+    else if ((AControl=nil) or (csDestroying in AControl.ComponentState)) then
       DockMaster.NeedFree(Self);
   end;
 end;
@@ -4577,7 +4851,8 @@
     Result:=Controls[i];
     if Result.Owner<>Self then exit;
   end;
-  Result:=nil;
+  result:=FMinimizedControl;
+  //Result:=nil;
 end;
 
 function TAnchorDockHostSite.GetSiteCount: integer;
@@ -5165,6 +5440,119 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;var AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+function TAnchorDockHostSite.CanBeMinimized(out Splitter: TAnchorDockSplitter;
+                                            out SplitterAnchorKind:TAnchorKind):boolean;
+var
+  AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+begin
+  result:=false;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) then
+      result:=true;
+  end
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+begin
+  //Application.QueueAsyncCall(@AsyncMinimizeSite,0);
+  AsyncMinimizeSite(0);
+end;
+
+procedure TAnchorDockHostSite.AsyncMinimizeSite(Data: PtrInt);
+var
+  AControl: TControl;
+  //OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  fMinimization:=true;
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  if FMinimized then
+    AControl:=FMinimizedControl
+  else
+    AControl:=GetOneControl;
+  if CanBeMinimized(Splitter,SplitterAnchorKind) or FMinimized then begin
+    FMinimized:=not FMinimized;
+    if FMinimized then begin
+      FMinimizedControl:=AControl;
+      AControl.Visible:=False;
+      AControl.Parent:=nil;
+      //self.DoDockOver(); OnDockOver;
+    end else begin
+      AControl.Parent:=self;
+      AControl.Visible:=True;
+      FMinimizedControl:=nil;
+    end;
+    Splitter.Enabled:=AControl.Visible;
+    UpdateHeaderAlign;
+    dockmaster.UpdateHeaders;
+    dockmaster.InvalidateHeaders;
+    Splitter.SetBoundsPercentually;
+  end;
+  fMinimization:=false;
+end;
+
+procedure TAnchorDockHostSite.ShowMinimizedControl;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  SpliterRect,OverlappingFormRect:TRect;
+begin
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    SpliterRect:=Splitter.GetSpliterBoundsWithUnminimizedDockSites;
+    OverlappingFormRect:=BoundsRect;
+    case SplitterAnchorKind of
+         akTop:OverlappingFormRect.Top:=SpliterRect.Bottom;
+        akLeft:OverlappingFormRect.Left:=SpliterRect.Right;
+       akRight:OverlappingFormRect.Right:=SpliterRect.Left;
+      akBottom:OverlappingFormRect.Bottom:=SpliterRect.Top;
+    end;
+    DockMaster.FOverlappingForm:=TAnchorDockOverlappingForm.CreateNew(self);
+    DockMaster.FOverlappingForm.BoundsRect:=OverlappingFormRect;
+    DockMaster.FOverlappingForm.Parent:=GetParentFormOrDockPanel(self,false);
+    DockMaster.FOverlappingForm.AnchorDockHostSite:=self;
+    header.Parent:=DockMaster.FOverlappingForm;
+    FMinimizedControl.Parent:=DockMaster.FOverlappingForm.Panel;
+    FMinimizedControl.Show;
+    DockMaster.ShowOverlappingForm;
+  end;
+end;
+
+procedure TAnchorDockHostSite.HideMinimizedControl;
+begin
+   FMinimizedControl.Hide;
+   header.Parent:=self;
+   header.UpdateHeaderControls;
+   FMinimizedControl.Parent:=nil;
+   FreeAndNil(DockMaster.FOverlappingForm);
+end;
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5281,21 +5669,24 @@
 begin
   if csDestroying in ComponentState then exit;
   NewCaption:='';
-  for i:=0 to ControlCount-1 do begin
-    Child:=Controls[i];
-    if Child=Exclude then continue;
-    if (Child.HostDockSite=Self) or (Child is TAnchorDockHostSite)
-    or (Child is TAnchorDockPageControl) then begin
-      if NewCaption<>'' then
-        NewCaption:=NewCaption+',';
-      NewCaption:=NewCaption+Child.Caption;
+  if FMinimized then
+    NewCaption:=FMinimizedControl.Caption
+  else
+    for i:=0 to ControlCount-1 do begin
+      Child:=Controls[i];
+      if Child=Exclude then continue;
+      if (Child.HostDockSite=Self) or (Child is TAnchorDockHostSite)
+      or (Child is TAnchorDockPageControl) then begin
+        if NewCaption<>'' then
+          NewCaption:=NewCaption+',';
+        NewCaption:=NewCaption+Child.Caption;
+      end;
     end;
-  end;
   OldCaption:=Caption;
   Caption:=NewCaption;
   //debugln(['TAnchorDockHostSite.UpdateDockCaption Caption="',Caption,'" NewCaption="',NewCaption,'" HasParent=',Parent<>nil,' ',DbgSName(Header)]);
-  if ((Parent=nil) and DockMaster.HideHeaderCaptionFloatingControl)
-  or (not DockMaster.ShowHeaderCaption) then
+  if {((Parent=nil) and DockMaster.HideHeaderCaptionFloatingControl)
+  or (not DockMaster.ShowHeaderCaption)}false then
     Header.Caption:=''
   else
     Header.Caption:=Caption;
@@ -5306,9 +5697,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm));
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5339,7 +5729,8 @@
   end;
 
   CanDock:=(Client is TAnchorDockHostSite)
-           and not DockMaster.AutoFreedIfControlIsRemoved(Self,Client);
+           and not DockMaster.AutoFreedIfControlIsRemoved(Self,Client)
+           and not FMinimized;
   //debugln(['TAnchorDockHostSite.GetSiteInfo ',DbgSName(Self),' ',dbgs(BoundsRect),' ',Caption,' CanDock=',CanDock,' PtIn=',PtInRect(InfluenceRect,MousePos)]);
 
   if Assigned(OnGetSiteInfo) then
@@ -5362,9 +5753,20 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      NeededHeaderPosition:=OppositeAnchorKind2TADLHeaderPosition[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5388,10 +5790,16 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderShowing;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  if HeaderNeedsShowing then
-    Header.Parent:=Self
+  if HeaderNeedsShowing then begin
+    Header.Parent:=Self;
+    Header.MinimizeButton.Visible:=(DockMaster.DockSitesCanBeMinimized and CanBeMinimized(Splitter,SplitterAnchorKind))or FMinimized;
+    Header.MinimizeButton.Parent:=Header;
+  end
   else
     Header.Parent:=nil;
 end;
@@ -5415,6 +5823,31 @@
   Result:=(fUpdateLayout>0) or (csDestroying in ComponentState);
 end;
 
+function AcceptAlign(Site:TAnchorDockHostSite; AlignCandidate:TAlign):TAlign;
+var
+  i:integer;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  MinimizedSiteAlign:TAlign;
+begin
+  for i:=0 to Site.ControlCount-1 do
+    if Site.Controls[i] is TAnchorDockHostSite then
+      if (Site.Controls[i] as TAnchorDockHostSite).FMinimized then begin
+        if FindNearestSpliter(Site.Controls[i] as TAnchorDockHostSite,Splitter,SplitterAnchorKind) then begin
+          MinimizedSiteAlign:=OppositeAnchorKind2Align[SplitterAnchorKind];
+          if AlignCandidate=MinimizedSiteAlign then
+            exit(alNone);
+        end
+      end;
+  result:=AlignCandidate;
+end;
+
+function TAnchorDockHostSite.GetDockEdge(const MousePos: TPoint): TAlign;
+begin
+  result:=inherited;
+  result:=AcceptAlign(self,result);
+end;
+
 procedure TAnchorDockHostSite.SaveLayout(
   LayoutTree: TAnchorDockLayoutTree; LayoutNode: TAnchorDockLayoutTreeNode);
 var
@@ -5432,7 +5865,7 @@
   if (SiteType=adhstOneControl) and (OneControl<>nil)
   and (not (OneControl is TAnchorDockHostSite)) then begin
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.Name:=OneControl.Name;
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if (SiteType in [adhstLayout,adhstOneControl]) then begin
@@ -5450,7 +5883,7 @@
         Splitter.SaveLayout(ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if SiteType=adhstPages then begin
     LayoutNode.NodeType:=adltnPages;
@@ -5461,7 +5894,7 @@
         Site.SaveLayout(LayoutTree,ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else
     LayoutNode.NodeType:=adltnNone;
@@ -5476,6 +5909,9 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
+  fMinimization:=false;
+  FMinimizedControl:=Nil;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5490,13 +5926,13 @@
 end;
 
 destructor TAnchorDockHostSite.Destroy;
-//var i: Integer;
+var i: Integer;
 begin
-  //debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
-  {for i:=0 to ComponentCount-1 do
+  debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
+  for i:=0 to ComponentCount-1 do
     debugln(['TAnchorDockHostSite.Destroy Component ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   for i:=0 to ControlCount-1 do
-    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);}
+    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);
   FreePages;
   inherited Destroy;
 end;
@@ -5562,13 +5998,34 @@
 end;
 
 procedure TAnchorDockHeader.CloseButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
 begin
-  if Parent is TAnchorDockHostSite then begin
-    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(Parent),true);
-    TAnchorDockHostSite(Parent).CloseSite;
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
   end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(HeaderParent),true);
+    HeaderParent.CloseSite;
+  end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
+begin
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
+  end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    HeaderParent.MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5635,11 +6092,18 @@
 
   if CloseButton.IsControlVisible and (CloseButton.Parent=Self) then begin
     if Align in [alLeft,alRight] then
-      r.Top:=CloseButton.Top+CloseButton.Height+1
+      r.Top:=CloseButton.Top+CloseButton.Height+ButtonBorderSpacingAround
     else
-      r.Right:=CloseButton.Left-1;
+      r.Right:=CloseButton.Left-ButtonBorderSpacingAround;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+ButtonBorderSpacingAround
+    else
+      r.Right:=MinimizeButton.Left-ButtonBorderSpacingAround;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,26 +6192,127 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
   X, Y: Integer);
+var
+  SiteMinimized:Boolean;
 begin
   inherited MouseDown(Button, Shift, X, Y);
-  if (Button=mbLeft) and DockMaster.AllowDragging then
-    DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
+  SiteMinimized:=False;
+  fUseTimer:=false;
+  StopMouseNoMoveTimer;
+  if Parent is TAnchorDockHostSite then
+    SiteMinimized:=(Parent as TAnchorDockHostSite).FMinimized;
+  if SiteMinimized then begin
+    DoMouseNoMoveTimer(nil);
+  end else
+    begin
+      if parent<>nil then
+        if DockMaster.FOverlappingForm<>nil then
+          //if parent=DockMaster.FOverlappingForm.Panel then
+            DockMaster.HideOverlappingForm(nil);
+      if (Button=mbLeft) and (DockMaster.AllowDragging) and (DockMaster.FOverlappingForm=nil) then
+        DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
+    end;
 end;
 
+procedure  TAnchorDockHeader.MouseMove(Shift: TShiftState; X,Y: Integer);
+begin
+  inherited MouseMove(Shift, X, Y);
+  if parent<>nil then
+    if parent is TAnchorDockHostSite then
+      if (parent as TAnchorDockHostSite).FMinimized then
+        if DockMaster.FOverlappingForm=nil then
+          if FMouseTimeStartX=EmptyMouseTimeStartX then
+            StartMouseNoMoveTimer(X, Y)
+          else begin
+            if (abs(FMouseTimeStartX-X)>MouseNoMoveDelta)or(abs(FMouseTimeStartY-Y)>MouseNoMoveDelta)then
+            StopMouseNoMoveTimer;
+          end;
+  if (parent is TAnchorDockHostSite)and(DockMaster.FOverlappingForm=nil)then
+    fUseTimer:=true;
+end;
+
+procedure TAnchorDockHeader.MouseLeave;
+begin
+  inherited;
+  StopMouseNoMoveTimer;
+end;
+
+procedure TAnchorDockHeader.StartMouseNoMoveTimer(X, Y: Integer);
+begin
+  if fUseTimer then begin
+    if DockTimer.Enabled then DockTimer.Enabled:=false;
+    DockTimer.Interval:=MouseNoMoveTime;
+    DockTimer.OnTimer:=@DoMouseNoMoveTimer;
+    DockTimer.Enabled:=true;
+  end;
+end;
+
+procedure TAnchorDockHeader.StopMouseNoMoveTimer;
+begin
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  DockTimer.OnTimer:=nil;
+  DockTimer.Enabled:=false;
+end;
+
+procedure TAnchorDockHeader.DoMouseNoMoveTimer(Sender: TObject);
+begin
+  StopMouseNoMoveTimer;
+  //if fUseTimer then
+    if parent<>nil then
+      if parent is TAnchorDockHostSite then
+        if (parent as TAnchorDockHostSite).FMinimized then
+          (parent as TAnchorDockHostSite).ShowMinimizedControl;
+end;
+
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
-      CloseButton.Align:=alTop;
+    if CloseButton<>nil then begin
+      //MinimizeButton.Align:=alTop;
+      //CloseButton.Align:=alTop;
+      CloseButton.AnchorSide[akRight].Side := asrCenter;
+      CloseButton.AnchorSide[akRight].Control := self;
+      CloseButton.AnchorSide[akTop].Side := asrTop;
+      CloseButton.AnchorSide[akTop].Control := self;
+      CloseButton.Anchors := CloseButton.Anchors + [akTop] + [akRight];
+
+      MinimizeButton.AnchorSide[akRight].Side := asrCenter;
+      MinimizeButton.AnchorSide[akRight].Control := CloseButton;
+      MinimizeButton.AnchorSide[akTop].Side := asrBottom;
+      MinimizeButton.AnchorSide[akTop].Control := CloseButton;
+      MinimizeButton.Anchors := MinimizeButton.Anchors + [akTop] + [akRight];
+    end;
   end else begin
-    if CloseButton<>nil then
-      CloseButton.Align:=alRight;
+    if CloseButton<>nil then begin
+      //MinimizeButton.Align:=alRight;
+      //CloseButton.Align:=alRight;
+      CloseButton.AnchorSide[akRight].Side := asrRight;
+      CloseButton.AnchorSide[akRight].Control := self;
+      CloseButton.AnchorSide[akTop].Side := asrCenter;
+      CloseButton.AnchorSide[akTop].Control := self;
+      CloseButton.Anchors := CloseButton.Anchors - [akLeft] + [akRight];
+
+      MinimizeButton.AnchorSide[akRight].Side := asrLeft;
+      MinimizeButton.AnchorSide[akRight].Control := CloseButton;
+      MinimizeButton.AnchorSide[akTop].Side := asrCenter;
+      MinimizeButton.AnchorSide[akTop].Control := CloseButton;
+      MinimizeButton.Anchors := MinimizeButton.Anchors - [akLeft] + [akRight];
+    end;
   end;
+  CloseButton.BorderSpacing.Around:=ButtonBorderSpacingAround;
+  MinimizeButton.BorderSpacing.Around:=ButtonBorderSpacingAround;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
 
@@ -5787,9 +6352,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,11 +6364,23 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
   PopupMenu:=DockMaster.GetPopupMenu;
   fFocused:=false;
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  fUseTimer:=true;
 end;
 
 { TAnchorDockCloseButton }
@@ -5830,6 +6407,31 @@
   Result := ThemeServices.GetElementDetails(WindowPart);
 end;
 
+procedure SizeCorrector(var current,recomend:integer);
+begin
+  if recomend<0 then begin
+    if current>0 then
+      recomend:=current
+    else
+      current:=HardcodedButtonSize;
+  end else begin
+      if current>recomend then
+        current:=recomend
+      else begin
+        if current>0 then
+         recomend:=current
+        else
+         current:=recomend;
+      end;
+  end;
+end;
+
+procedure ButtonSizeCorrector(var w,h:integer);
+begin
+  SizeCorrector(w,PreferredButtonWidth);
+  SizeCorrector(h,PreferredButtonHeight);
+end;
+
 procedure TAnchorDockCloseButton.CalculatePreferredSize(var PreferredWidth,
   PreferredHeight: integer; WithThemeSpace: Boolean);
 begin
@@ -5837,6 +6439,7 @@
   begin
     PreferredWidth:=cx;
     PreferredHeight:=cy;
+    ButtonSizeCorrector(PreferredWidth,PreferredHeight);
     {$IF defined(LCLGtk2) or defined(Carbon)}
     inc(PreferredWidth,2);
     inc(PreferredHeight,2);
@@ -5844,6 +6447,45 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMinButtonNormal;
+    if not IsEnabled then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonDisabled{$ELSE}twMinButtonDisabled{$ENDIF}
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonPushed{$ELSE}twMinButtonPushed{$ENDIF}
+    else
+    if FState = bsHot then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonHot{$ELSE}twMinButtonHot{$ENDIF}
+    else
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF};
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails({$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF})) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    ButtonSizeCorrector(PreferredWidth,PreferredHeight);
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6213,6 +6855,9 @@
   ClientRectChanged:=(WidthDiff<>0) or (HeightDiff<>0);
   if ClientRectChanged or PreferredSiteSizeAsSiteMinimum then
     AlignChilds;
+  if ClientRectChanged then
+    if DockMaster.FOverlappingForm<>nil then
+      DockMaster.HideOverlappingForm(nil);
 end;
 
 procedure TAnchorDockManager.SaveToStream(Stream: TStream);
@@ -6287,6 +6932,11 @@
       ADockObject.DropOnControl:=Site
     else
       ADockObject.DropOnControl:=nil;
+    if Site is TAnchorDockHostSite then begin
+      ADockObject.DropAlign:=AcceptAlign(Site as TAnchorDockHostSite,ADockObject.DropAlign);
+      if ADockObject.DropAlign=alNone then
+        exit(false);
+    end;
   end;
   //debugln(['TAnchorDockManager.GetDockEdge ADockObject.DropAlign=',dbgs(ADockObject.DropAlign),' DropOnControl=',DbgSName(ADockObject.DropOnControl)]);
   Result:=true;
@@ -6505,32 +7155,58 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
@@ -6560,14 +7236,47 @@
   end;
 end;
 
+function TAnchorDockSplitter.GetSpliterBoundsWithUnminimizedDockSites:TRect;
+var
+  NewLeft, NewTop: Integer;
+begin
+  if ResizeAnchor in [akLeft,akRight] then
+  begin
+    if DockParentClientSize.cx> 0 then
+    begin
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+      else
+        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+      NewTop := Top;
+    end;
+  end else
+  begin
+    if DockParentClientSize.cy> 0 then
+    begin
+      NewLeft := Left;
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewTop := Round(FPercentPosition*Parent.ClientHeight)
+      else
+        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    end;
+  end;
+  result:=Rect(NewLeft,NewTop,NewLeft+Width,NewTop+Height);
+end;
+
 procedure TAnchorDockSplitter.SaveLayout(
   LayoutNode: TAnchorDockLayoutTreeNode);
+var
+  NewLeft, NewTop: Integer;
 begin
   if ResizeAnchor in [akLeft,akRight] then
     LayoutNode.NodeType:=adltnSplitterVertical
   else
     LayoutNode.NodeType:=adltnSplitterHorizontal;
-  LayoutNode.Assign(Self);
+  LayoutNode.Assign(Self,false,false);
+  if not Enabled then begin
+    LayoutNode.BoundsRect:=GetSpliterBoundsWithUnminimizedDockSites;
+  end
 end;
 
 function TAnchorDockSplitter.HasOnlyOneSibling(Side: TAnchorKind; MinPos,
@@ -6645,7 +7354,7 @@
 begin
   inherited MouseDown(Button, Shift, X, Y);
   ATabIndex := IndexOfPageAt(X, Y);
-  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) then
+  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) and (DockMaster.FOverlappingForm=nil) then
   begin
     APage:=Page[ATabIndex];
     if (APage.ControlCount>0) and (APage.Controls[0] is TAnchorDockHostSite) then
@@ -6782,6 +7491,20 @@
   PopupMenu:=DockMaster.GetPopupMenu;
 end;
 
+{ TAnchorDockOverlappingForm }
+
+constructor TAnchorDockOverlappingForm.CreateNew(AOwner: TComponent; Num: Integer = 0);
+begin
+  inherited;
+  BorderStyle:=bsNone;
+  AnchorDockHostSite:=nil;
+  Panel:=TPanel.Create(self);
+  Panel.BorderStyle:=bsSingle;
+  Panel.Align:=alClient;
+  Panel.Parent:=self;
+  Panel.Visible:=true;
+end;
+
 { TAnchorDockPage }
 
 procedure TAnchorDockPage.UpdateDockCaption(Exclude: TControl);
@@ -6835,9 +7558,11 @@
 
 initialization
   DockMaster:=TAnchorDockMaster.Create(nil);
+  DockTimer:=TTimer.Create(nil);
 
 finalization
   FreeAndNil(DockMaster);
+  FreeAndNil(DockTimer);
 
 end.
 
Index: components/anchordocking/anchordockoptionsdlg.lfm
===================================================================
--- components/anchordocking/anchordockoptionsdlg.lfm	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.lfm	(working copy)
@@ -1,11 +1,13 @@
 object AnchorDockOptionsFrame: TAnchorDockOptionsFrame
   Left = 0
-  Height = 482
+  Height = 567
   Top = 0
-  Width = 416
-  ClientHeight = 482
-  ClientWidth = 416
+  Width = 490
+  ClientHeight = 567
+  ClientWidth = 490
+  DesignTimePPI = 113
   OnClick = FrameClick
+  ParentFont = False
   TabOrder = 0
   DesignLeft = 513
   DesignTop = 189
@@ -12,14 +14,15 @@
   object DragThresholdLabel: TLabel
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
-    Left = 10
-    Height = 13
-    Top = 10
-    Width = 111
-    BorderSpacing.Left = 10
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 12
+    Width = 122
+    BorderSpacing.Left = 12
+    BorderSpacing.Top = 12
     Caption = 'DragThresholdLabel'
     ParentColor = False
+    ParentFont = False
   end
   object DragThresholdTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdLabel
@@ -27,15 +30,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 23
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 31
+    Width = 466
     Max = 20
     OnChange = DragThresholdTrackBarChange
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Right = 10
+    BorderSpacing.Right = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 1
@@ -46,12 +50,13 @@
     AnchorSideTop.Control = DragThresholdLabel
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
-    Left = 127
-    Height = 23
-    Top = 5
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 141
+    Height = 27
+    Top = 8
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 20
+    ParentFont = False
     TabOrder = 0
     Visible = False
   end
@@ -59,13 +64,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = DragThresholdTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 79
-    Width = 103
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 97
+    Width = 112
+    BorderSpacing.Top = 12
     Caption = 'SplitterWidthLabel'
     ParentColor = False
+    ParentFont = False
   end
   object SplitterWidthTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdTrackBar
@@ -73,14 +79,15 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 92
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 116
+    Width = 466
     Min = 1
     OnChange = SplitterWidthTrackBarChange
     Position = 1
     Anchors = [akTop, akLeft, akRight]
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 3
@@ -89,12 +96,13 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = SplitterWidthTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 142
-    Width = 160
-    BorderSpacing.Top = 4
+    Left = 12
+    Height = 23
+    Top = 175
+    Width = 169
+    BorderSpacing.Top = 5
     Caption = 'ScaleOnResizeCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 4
@@ -103,12 +111,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 166
-    Width = 149
+    Left = 12
+    Height = 23
+    Top = 198
+    Width = 160
     Caption = 'ShowHeaderCheckBox'
     OnChange = ShowHeaderCheckBoxChange
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 5
@@ -117,12 +126,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ShowHeaderCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 190
-    Width = 191
-    BorderSpacing.Left = 15
+    Left = 30
+    Height = 23
+    Top = 221
+    Width = 208
+    BorderSpacing.Left = 18
     Caption = 'ShowHeaderCaptionCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 6
@@ -131,11 +141,12 @@
     AnchorSideLeft.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 214
-    Width = 249
+    Left = 30
+    Height = 23
+    Top = 244
+    Width = 272
     Caption = 'HideHeaderCaptionForFloatingCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 7
@@ -147,15 +158,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 122
+    Left = 136
     Height = 27
-    Top = 286
-    Width = 284
+    Top = 313
+    Width = 342
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 6
-    BorderSpacing.Right = 10
-    ItemHeight = 0
+    BorderSpacing.Left = 7
+    BorderSpacing.Right = 12
+    ItemHeight = 19
     OnDrawItem = HeaderStyleComboBoxDrawItem
+    ParentFont = False
     Style = csDropDownList
     TabOrder = 10
   end
@@ -163,23 +175,25 @@
     AnchorSideLeft.Control = ShowHeaderCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrCenter
-    Left = 20
-    Height = 13
-    Top = 293
-    Width = 96
-    BorderSpacing.Left = 10
+    Left = 24
+    Height = 19
+    Top = 317
+    Width = 105
+    BorderSpacing.Left = 12
     Caption = 'HeaderStyleLabel'
     ParentColor = False
+    ParentFont = False
   end
   object FlattenHeadersCheckBox: TCheckBox
     AnchorSideLeft.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 238
-    Width = 164
+    Left = 30
+    Height = 23
+    Top = 267
+    Width = 175
     Caption = 'FlattenHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 8
@@ -188,11 +202,12 @@
     AnchorSideLeft.Control = FlattenHeadersCheckBox
     AnchorSideTop.Control = FlattenHeadersCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 262
-    Width = 154
+    Left = 30
+    Height = 23
+    Top = 290
+    Width = 164
     Caption = 'FilledHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 9
@@ -201,11 +216,12 @@
     AnchorSideLeft.Control = FilledHeadersCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 313
-    Width = 175
+    Left = 30
+    Height = 23
+    Top = 340
+    Width = 189
     Caption = 'HighlightFocusedCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 11
@@ -215,13 +231,14 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = SplitterWidthLabel
     AnchorSideTop.Side = asrCenter
-    Left = 119
-    Height = 23
-    Top = 74
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 131
+    Height = 27
+    Top = 93
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 10
     MinValue = 1
+    ParentFont = False
     TabOrder = 2
     Value = 1
     Visible = False
@@ -228,15 +245,16 @@
   end
   object HeaderAlignTopLabel: TLabel
     AnchorSideLeft.Control = DragThresholdLabel
-    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Control = DockSitesCanBeMinimized
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 347
-    Width = 117
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 398
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignTopLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignTopTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -244,10 +262,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 360
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 417
+    Width = 466
     Frequency = 10
     Max = 150
     OnChange = HeaderAlignTopTrackBarChange
@@ -254,7 +272,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 13
@@ -264,12 +283,13 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignTopLabel
     AnchorSideTop.Side = asrCenter
-    Left = 133
-    Height = 23
-    Top = 342
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 394
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 150
+    ParentFont = False
     TabOrder = 12
     Visible = False
   end
@@ -277,13 +297,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = HeaderAlignTopTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 417
-    Width = 120
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 484
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignLeftLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignLeftTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -291,10 +312,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 430
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 503
+    Width = 466
     Frequency = 10
     Max = 200
     OnChange = HeaderAlignLeftTrackBarChange
@@ -301,7 +322,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 15
@@ -311,13 +333,28 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignLeftLabel
     AnchorSideTop.Side = asrCenter
-    Left = 136
-    Height = 23
-    Top = 412
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 480
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 200
+    ParentFont = False
     TabOrder = 14
     Visible = False
   end
+  object DockSitesCanBeMinimized: TCheckBox
+    AnchorSideLeft.Control = FilledHeadersCheckBox
+    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Side = asrBottom
+    Left = 30
+    Height = 23
+    Top = 363
+    Width = 185
+    Caption = 'DockSitesCanBeMinimized'
+    ParentFont = False
+    ParentShowHint = False
+    ShowHint = True
+    TabOrder = 16
+  end
 end
Index: components/anchordocking/anchordockoptionsdlg.pas
===================================================================
--- components/anchordocking/anchordockoptionsdlg.pas	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.pas	(working copy)
@@ -37,6 +37,7 @@
     HeaderStyleLabel: TLabel;
     HideHeaderCaptionForFloatingCheckBox: TCheckBox;
     HighlightFocusedCheckBox: TCheckBox;
+    DockSitesCanBeMinimized: TCheckBox;
     ScaleOnResizeCheckBox: TCheckBox;
     ShowHeaderCaptionCheckBox: TCheckBox;
     ShowHeaderCheckBox: TCheckBox;
@@ -202,7 +203,7 @@
 
       HeaderAlignTopSpinEdit.Visible:=true;
       HeaderAlignTopTrackBar.Visible:=false;
-      HeaderAlignTopSpinEdit.AnchorToNeighbour(akTop,6,HighlightFocusedCheckBox);
+      HeaderAlignTopSpinEdit.AnchorToNeighbour(akTop,6,DockSitesCanBeMinimized);
       HeaderAlignTopLabel.AnchorVerticalCenterTo(HeaderAlignTopSpinEdit);
       UpdateHeaderAlignTopLabel;
 
@@ -299,6 +300,7 @@
   HeaderStyleLabel.Enabled:=HasHeaders;
   HeaderStyleComboBox.Enabled:=HasHeaders;
   HighlightFocusedCheckBox.Enabled:=HasHeaders;
+  DockSitesCanBeMinimized.Enabled:=HasHeaders;
 end;
 
 constructor TAnchorDockOptionsFrame.Create(TheOwner: TComponent);
@@ -356,6 +358,7 @@
   TheSettings.HeaderFilled:=FilledHeadersCheckBox.Checked;
   TheSettings.HeaderStyle:=TADHeaderStyle(HeaderStyleComboBox.ItemIndex);
   TheSettings.HeaderHighlightFocused:=HighlightFocusedCheckBox.Checked;
+  TheSettings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized.Checked;
 end;
 
 procedure TAnchorDockOptionsFrame.LoadFromSettings(
@@ -429,6 +432,10 @@
   HighlightFocusedCheckBox.Checked:=TheSettings.HeaderHighlightFocused;
   HighlightFocusedCheckBox.Caption:=adrsHighlightFocused;
   HighlightFocusedCheckBox.Hint:=adrsHighlightFocusedHint;
+
+  DockSitesCanBeMinimized.Checked:=TheSettings.DockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Caption:=adrsDockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Hint:=adrsDockSitesCanBeMinimizedHint;
 end;
 
 end.
Index: components/anchordocking/anchordockpanel.pas
===================================================================
--- components/anchordocking/anchordockpanel.pas	(revision 59428)
+++ components/anchordocking/anchordockpanel.pas	(working copy)
@@ -55,7 +55,7 @@
   begin
 
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,false);
     LayoutNode.Name:={OneControl.}Name;
 
     TAnchorDockHostSite(OneControl).SaveLayout(LayoutTree,LayoutNode);
Index: components/anchordocking/anchordockstorage.pas
===================================================================
--- components/anchordocking/anchordockstorage.pas	(revision 59428)
+++ components/anchordocking/anchordockstorage.pas	(working copy)
@@ -64,6 +64,7 @@
     FTabPosition: TTabPosition;
     FWindowState: TWindowState;
     FControlLocation: TADLControlLocation;
+    FMinimized: Boolean;
     function GetAnchors(Site: TAnchorKind): string;
     function GetBottom: integer;
     function GetHeight: integer;
@@ -90,6 +91,7 @@
     procedure SetTop(const AValue: integer);
     procedure SetWidth(const AValue: integer);
     procedure SetWindowState(const AValue: TWindowState);
+    procedure SetMinimized(const AValue: boolean);
   public
     constructor Create;
     destructor Destroy; override;
@@ -96,7 +98,7 @@
     procedure Clear;
     function IsEqual(Node: TAnchorDockLayoutTreeNode): boolean;
     procedure Assign(Node: TAnchorDockLayoutTreeNode); overload;
-    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean=false); overload;
+    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean); overload;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
     procedure LoadFromConfig(Path: string; Config: TRttiXMLConfig); overload;
     procedure SaveToConfig(Config: TConfigStorage); overload;
@@ -106,7 +108,7 @@
     procedure CheckConsistency; virtual;
 
     // simplifying
-    procedure Simplify(ExistingNames: TStrings);
+    procedure Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
     procedure DeleteNode(ChildNode: TAnchorDockLayoutTreeNode);
     function FindNodeBoundSplitter(ChildNode: TAnchorDockLayoutTreeNode;
                                    Side: TAnchorKind): TAnchorDockLayoutTreeNode;
@@ -135,6 +137,7 @@
     property Monitor: integer read FMonitor write SetMonitor;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property TabPosition: TTabPosition read FTabPosition write SetTabPosition;
+    property Minimized: Boolean read FMinimized write SetMinimized;
     function Count: integer;
     function IsSplitter: boolean;
     function IsRootWindow: boolean;
@@ -988,6 +991,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockLayoutTreeNode.SetMinimized(const AValue: boolean);
+begin
+  if FMinimized=AValue then exit;
+  FMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockLayoutTreeNode.SetTop(const AValue: integer);
 begin
   if Top=AValue then exit;
@@ -1084,6 +1094,7 @@
   BoundSplitterPos:=Node.BoundSplitterPos;
   WorkAreaRect:=Node.WorkAreaRect;
   Monitor:=Node.Monitor;
+  Minimized:=Node.Minimized;
   for a:=low(TAnchorKind) to high(TAnchorKind) do
     Anchors[a]:=Node.Anchors[a];
   while Count>Node.Count do Nodes[Count-1].Free;
@@ -1098,9 +1109,10 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean=false);
+procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean);
 var
   AnchorControl: TControl;
+  ParentForm:TCustomForm;
   a: TAnchorKind;
 begin
   Name:=AControl.Name;
@@ -1109,12 +1121,18 @@
   else
     BoundsRect:=AControl.BoundsRect;
   Align:=AControl.Align;
+  Minimized:=AMinimized;
   if (AControl.Parent=nil) and (AControl is TCustomForm) then begin
     WindowState:=TCustomForm(AControl).WindowState;
     Monitor:=TCustomForm(AControl).Monitor.MonitorNum;
     WorkAreaRect:=TCustomForm(AControl).Monitor.WorkareaRect;
-  end else
-    WindowState:=GetParentForm(AControl).WindowState;
+  end else begin
+    ParentForm:=GetParentForm(AControl);
+    if assigned(ParentForm) then
+      WindowState:=ParentForm.WindowState
+    else
+      WindowState:=wsNormal;
+  end;
   if AControl is TCustomTabControl then
     TabPosition:=TCustomTabControl(AControl).TabPosition
   else
@@ -1137,6 +1155,7 @@
   Clear;
   Name:=Config.GetValue('Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue('Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue('Minimized',false);
   Left:=Config.GetValue('Bounds/Left',0);
   Top:=Config.GetValue('Bounds/Top',0);
   Width:=Config.GetValue('Bounds/Width',0);
@@ -1171,6 +1190,7 @@
   Clear;
   Name:=Config.GetValue(Path+'Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue(Path+'Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue(Path+'Minimized',false);
   Left:=Config.GetValue(Path+'Bounds/Left',0);
   Top:=Config.GetValue(Path+'Bounds/Top',0);
   Width:=Config.GetValue(Path+'Bounds/Width',0);
@@ -1219,6 +1239,7 @@
                                           ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue('Header/TabPosition',ADLTabPostionNames[TabPosition],
                                              ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue('Minimized',Minimized,False);
   Config.SetDeleteValue('Monitor',Monitor,0);
   Config.SetDeleteValue('ChildCount',Count,0);
   for i:=1 to Count do begin
@@ -1252,6 +1273,7 @@
                                                ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue(Path+'Header/TabPosition',ADLTabPostionNames[TabPosition],
                                                   ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue(Path+'Minimized',Minimized,False);
   Config.SetDeleteValue(Path+'Monitor',Monitor,0);
   Config.SetDeleteValue(Path+'ChildCount',Count,0);
   for i:=1 to Count do
@@ -1397,7 +1419,7 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings);
+procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
 { Simplification rules:
    1. Control nodes without existing name are deleted.
    2. Empty layouts and pages are deleted
@@ -1406,16 +1428,18 @@
 var
   i: Integer;
   ChildNode: TAnchorDockLayoutTreeNode;
+  NodeMinimized:boolean;
 begin
   // simplify children
   i:=Count-1;
   while i>=0 do begin
     ChildNode:=Nodes[i];
-    ChildNode.Simplify(ExistingNames);
+    NodeMinimized:=ParentMinimized or ChildNode.Minimized;
+    ChildNode.Simplify(ExistingNames,NodeMinimized);
 
     if (ChildNode.NodeType=adltnControl) then begin
       // leaf node => check if there is a control
-      if (ChildNode.Name='') or (ExistingNames.IndexOf(ChildNode.Name)<0) then
+      if (ChildNode.Name='') or ((ExistingNames.IndexOf(ChildNode.Name)<0) and (not NodeMinimized)) then
         DeleteNode(ChildNode);
     end else if ChildNode.IsSplitter then begin
       // splitter
@@ -1424,7 +1448,7 @@
         ChildNode[0].Free;
     end else if ChildNode.NodeType=adltnCustomSite then begin
       // custom dock site
-    end else if ChildNode.Count=0 then begin
+    end else if (ChildNode.Count=0)and(not NodeMinimized) then begin
       // inner node without child => delete
       DeleteNode(ChildNode);
     end else if (ChildNode.Count=1)
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59428)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';
@@ -82,6 +83,8 @@
   adrsFilledHeadersHint = 'Fill headers of docked controls';
   adrsHighlightFocused = 'Highlight focused';
   adrsHighlightFocusedHint = 'Highlight header of focused docked control';
+  adrsDockSitesCanBeMinimized = 'Dock sites can be minimized';
+  adrsDockSitesCanBeMinimizedHint = 'Dock sites can be minimized';
 
 implementation
 
Index: components/anchordocking/design/anchordesktopoptions.pas
===================================================================
--- components/anchordocking/design/anchordesktopoptions.pas	(revision 59428)
+++ components/anchordocking/design/anchordesktopoptions.pas	(working copy)
@@ -272,7 +272,7 @@
         // custom dock site
         LayoutNode:=FTree.NewNode(FTree.Root);
         LayoutNode.NodeType:=adltnCustomSite;
-        LayoutNode.Assign(AForm);
+        LayoutNode.Assign(AForm,false,false);
         // can have one normal dock site
         Site:=TAnchorDockManager(AForm.DockManager).GetChildSite;
         if Site<>nil then begin
@@ -287,7 +287,7 @@
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    FTree.Root.Simplify(VisibleControls);
+    FTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;
Index: lcl/include/dragmanager.inc
===================================================================
--- lcl/include/dragmanager.inc	(revision 59428)
+++ lcl/include/dragmanager.inc	(working copy)
@@ -484,6 +484,8 @@
         else
           DropAlign := DropOnControl.GetDockEdge(DropOnControl.ScreenToClient(APosition));
       end;
+      if DropAlign=alNone then
+        ATarget:=nil;
     end;
 
   if ATarget <> FDockObject.DragTarget then

<?xml version="1.0" encoding="utf-8"?>
<CONFIG>
  <MainConfig>
    <Nodes ChildCount="1">
      <Item1 Name="MainIDE" Type="CustomSite" ChildCount="1">
        <Bounds Top="50" Left="100" Width="722" Height="502">
          <WorkArea>
            <Rect Right="1920" Bottom="1036"/>
          </WorkArea>
        </Bounds>
        <Item1 Name="AnchorDockSite6" Type="Layout" ChildCount="9">
          <Bounds Top="58" Width="722" Height="420" SplitterPos="53"/>
          <Anchors Align="Bottom"/>
          <Item1 Name="ObjectInspector" Type="Control">
            <Bounds Width="177" Height="420"/>
            <Anchors Right="AnchorDockSplitter2"/>
          </Item1>
          <Item2 Name="AnchorDockSplitter2" Type="SplitterVertical">
            <Bounds Left="177" Width="4" Height="420"/>
          </Item2>
          <Item3 Name="SourceEditor1" Type="Control">
            <Bounds Left="181" Width="160" Height="420"/>
            <Anchors Left="AnchorDockSplitter2" Right="AnchorDockSplitter4"/>
          </Item3>
          <Item4 Name="FPDocEditor" Type="Control">
            <Bounds Left="632" Width="90" Height="420"/>
            <Anchors Left="AnchorDockSplitter3"/>
          </Item4>
          <Item5 Name="AnchorDockSplitter4" Type="SplitterVertical">
            <Bounds Left="341" Width="4" Height="420"/>
          </Item5>
          <Item6 Name="Messages" Type="Control" Minimized="True">
            <Bounds Left="345" Width="15" Height="420"/>
            <Anchors Left="AnchorDockSplitter4" Right="AnchorDockSplitter5"/>
          </Item6>
          <Item7 Name="AnchorDockSplitter5" Type="SplitterVertical">
            <Bounds Left="522" Width="4" Height="420"/>
          </Item7>
          <Item8 Name="ProjectInspector" Type="Control">
            <Bounds Left="364" Width="264" Height="420"/>
            <Anchors Left="AnchorDockSplitter5" Right="AnchorDockSplitter3"/>
          </Item8>
          <Item9 Name="AnchorDockSplitter3" Type="SplitterVertical">
            <Bounds Left="628" Width="4" Height="420"/>
          </Item9>
        </Item1>
      </Item1>
    </Nodes>
  </MainConfig>
  <Settings DockSitecCanBeMinimized="True"/>
</CONFIG>

Index: components/anchordocking/anchordocking.pas
===================================================================
--- components/anchordocking/anchordocking.pas	(revision 59428)
+++ components/anchordocking/anchordocking.pas	(working copy)
@@ -109,6 +109,37 @@
 const ADAutoSizingReason = 'TAnchorDockMaster Delayed';
 {$ENDIF}
 
+const EmptyMouseTimeStartX=low(Integer);
+      MouseNoMoveDelta=5;
+      MouseNoMoveTime=500;
+      HideOverlappingFormByMouseLoseTime=500;
+      ButtonBorderSpacingAround=4;
+      OppositeAnchorKind2Align: array[TAnchorKind] of TAlign = (
+        alBottom, // akTop,
+        alRight,  // akLeft,
+        alLeft,   // akRight,
+        alTop     // akBottom
+        );
+      OppositeAnchorKind: array[TAnchorKind] of TAnchorKind = (
+        akBottom, // akTop,
+        akRight,  // akLeft,
+        akLeft,   // akRight,
+        akTop     // akBottom
+        );
+      {AnchorKind2Align: array[TAnchorKind] of TAlign = (
+        alTop,  // akTop,
+        alLeft, // akLeft,
+        alRight,// akRight,
+        alBottom// akBottom
+        );}
+      OppositeAnchorKind2TADLHeaderPosition: array[TAnchorKind] of TADLHeaderPosition = (
+        adlhpBottom, // akTop,
+        adlhpRight,  // akLeft,
+        adlhpLeft,   // akRight,
+        adlhpTop     // akBottom
+        );
+
+
 type
   TAnchorDockHostSite = class;
 
@@ -123,6 +154,14 @@
            PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
   end;
 
+  TAnchorDockMinimizeButton = class(TCustomSpeedButton)
+  protected
+    function GetDrawDetails: TThemedElementDetails; override;
+    procedure CalculatePreferredSize(var PreferredWidth,
+           PreferredHeight: integer; {%H-}WithThemeSpace: Boolean); override;
+  end;
+
+
   { TAnchorDockHeader
     The panel of a TAnchorDockHostSite containing the close button and the
     caption when the form is docked. The header can be shown at any of the four
@@ -133,9 +172,13 @@
   TAnchorDockHeader = class(TCustomPanel)
   private
     FCloseButton: TCustomSpeedButton;
+    FMinimizeButton: TCustomSpeedButton;
     FHeaderPosition: TADLHeaderPosition;
     fFocused:Boolean;
+    fUseTimer:Boolean;
+    FMouseTimeStartX,FMouseTimeStartY:Integer;
     procedure CloseButtonClick(Sender: TObject);
+    procedure MinimizeButtonClick(Sender: TObject);
     procedure HeaderPositionItemClick(Sender: TObject);
     procedure UndockButtonClick(Sender: TObject);
     procedure MergeButtonClick(Sender: TObject);
@@ -147,6 +190,11 @@
           PreferredHeight: integer; WithThemeSpace: Boolean); override;
     procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X,
              Y: Integer); override;
+    procedure MouseMove(Shift: TShiftState; X,Y: Integer); override;
+    procedure MouseLeave;  override;
+    procedure StartMouseNoMoveTimer(X, Y: Integer);
+    procedure StopMouseNoMoveTimer;
+    procedure DoMouseNoMoveTimer(Sender: TObject);
     procedure UpdateHeaderControls;
     procedure SetAlign(Value: TAlign); override;
     procedure DoOnShowHint(HintInfo: PHintInfo); override;
@@ -154,6 +202,7 @@
   public
     constructor Create(TheOwner: TComponent); override;
     property CloseButton: TCustomSpeedButton read FCloseButton;
+    property MinimizeButton: TCustomSpeedButton read FMinimizeButton;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property BevelOuter default bvNone;
   end;
@@ -190,6 +239,7 @@
     procedure SetBoundsKeepDockBounds(ALeft, ATop, AWidth, AHeight: integer); // movement for scaling keeps the DockBounds
     function SideAnchoredControlCount(Side: TAnchorKind): integer;
     function HasAnchoredControls: boolean;
+    function GetSpliterBoundsWithUnminimizedDockSites:TRect;
     procedure SaveLayout(LayoutNode: TAnchorDockLayoutTreeNode);
     function HasOnlyOneSibling(Side: TAnchorKind; MinPos, MaxPos: integer): TControl;
     property DockRestoreBounds: TRect read FDockRestoreBounds write FDockRestoreBounds;
@@ -241,6 +291,14 @@
   end;
   TAnchorDockPageControlClass = class of TAnchorDockPageControl;
 
+
+  TAnchorDockOverlappingForm = class(TCustomForm)
+  public
+    AnchorDockHostSite:TAnchorDockHostSite;
+    Panel:TPanel;
+    constructor CreateNew(AOwner: TComponent; Num: Integer = 0); override;
+  end;
+
   { TAnchorDockHostSite
     This form is the dockhostsite for all controls.
     When docked together they build a tree structure with the docked controls
@@ -262,7 +320,10 @@
     FPages: TAnchorDockPageControl;
     FSiteType: TAnchorDockHostSiteType;
     FBoundSplitter: TAnchorDockSplitter;
-    fUpdateLayout: integer;
+    fUpdateLayout: Integer;
+    FMinimized: Boolean;
+    fMinimization: Boolean;
+    FMinimizedControl: TControl;
     procedure SetHeaderSide(const AValue: TAnchorKind);
   protected
     procedure DoEnter; override;
@@ -319,6 +380,10 @@
     destructor Destroy; override;
     function CloseQuery: boolean; override;
     function CloseSite: boolean; virtual;
+    procedure MinimizeSite; virtual;
+    procedure AsyncMinimizeSite(Data: PtrInt);
+    procedure ShowMinimizedControl;
+    procedure HideMinimizedControl;
     procedure RemoveControl(AControl: TControl); override;
     procedure InsertControl(AControl: TControl; Index: integer); override;
     procedure GetSiteInfo(Client: TControl; var InfluenceRect: TRect;
@@ -329,6 +394,7 @@
     procedure UpdateDockCaption(Exclude: TControl = nil); override;
     procedure UpdateHeaderAlign;
     procedure UpdateHeaderShowing;
+    function CanBeMinimized(out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
     procedure BeginUpdateLayout;
     procedure EndUpdateLayout;
     function UpdatingLayout: boolean;
@@ -337,6 +403,7 @@
     procedure SaveLayout(LayoutTree: TAnchorDockLayoutTree;
                          LayoutNode: TAnchorDockLayoutTreeNode);
     property DockRestoreBounds: TRect read FDockRestoreBounds write FDockRestoreBounds;
+    function GetDockEdge(const MousePos: TPoint): TAlign; override;
 
     property HeaderSide: TAnchorKind read FHeaderSide write SetHeaderSide;
     property Header: TAnchorDockHeader read FHeader;
@@ -431,6 +498,7 @@
     FShowHeader: boolean;
     FShowHeaderCaption: boolean;
     FSplitterWidth: integer;
+    FDockSitecCanBeMinimized: boolean;
     procedure SetAllowDragging(AValue: boolean);
     procedure SetDockOutsideMargin(AValue: integer);
     procedure SetDockParentMargin(AValue: integer);
@@ -448,6 +516,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitecCanBeMinimized(AValue: boolean);
   public
     property DragTreshold: integer read FDragTreshold write SetDragTreshold;
     property DockOutsideMargin: integer read FDockOutsideMargin write SetDockOutsideMargin;
@@ -466,6 +535,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused;
+    property DockSitesCanBeMinimized: boolean read FDockSitecCanBeMinimized write SetDockSitecCanBeMinimized;
     procedure IncreaseChangeStamp; inline;
     property ChangeStamp: integer read FChangeStamp;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
@@ -502,6 +572,7 @@
     FHeaderFlatten: boolean;
     FHeaderFilled: boolean;
     FHeaderHighlightFocused: boolean;
+    FDockSitesCanBeMinimized: boolean;
     FIdleConnected: Boolean;
     FManagerClass: TAnchorDockManagerClass;
     FOnCreateControl: TADCreateControlEvent;
@@ -531,6 +602,7 @@
     fPopupMenu: TPopupMenu;
     // Used by RestoreLayout:
     WorkArea, SrcWorkArea: TRect;
+    FOverlappingForm:TAnchorDockOverlappingForm;
 
     function GetControls(Index: integer): TControl;
     function GetLocalizedHeaderHint: string;
@@ -541,6 +613,9 @@
     function GetNodeSite(Node: TAnchorDockLayoutTreeNode): TAnchorDockHostSite;
     procedure MapTreeToControls(Tree: TAnchorDockLayoutTree);
     function RestoreLayout(Tree: TAnchorDockLayoutTree; Scale: boolean): boolean;
+    procedure SetMinimizedState(Tree: TAnchorDockLayoutTree);
+    procedure UpdateHeaders;
+    procedure SetnodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
     procedure EnableAllAutoSizing;
     procedure ClearLayoutProperties(AControl: TControl; NewAlign: TAlign = alClient);
     procedure PopupMenuPopup(Sender: TObject);
@@ -561,6 +636,7 @@
     procedure SetHeaderFlatten(AValue: boolean);
     procedure SetHeaderFilled(AValue: boolean);
     procedure SetHeaderHighlightFocused(AValue: boolean);
+    procedure SetDockSitesCanBeMinimized(AValue: boolean);
 
     procedure SetShowMenuItemShowHeader(AValue: boolean);
     procedure SetupSite(Site: TWinControl; ANode: TAnchorDockLayoutTreeNode;
@@ -584,8 +660,12 @@
     procedure SetHideHeaderCaptionFloatingControl(const AValue: boolean);
     procedure SetSplitterWidth(const AValue: integer);
     procedure OnIdle(Sender: TObject; var Done: Boolean);
+    procedure StartHideOverlappingTimer;
+    procedure StopHideOverlappingTimer;
     procedure AsyncSimplify({%H-}Data: PtrInt);
   public
+    procedure ShowOverlappingForm;
+    procedure HideOverlappingForm(Sender: TObject);
     constructor Create(AOwner: TComponent); override;
     destructor Destroy; override;
     function FullRestoreLayout(Tree: TAnchorDockLayoutTree; Scale: Boolean): Boolean;
@@ -680,6 +760,7 @@
     property HeaderFlatten: boolean read FHeaderFlatten write SetHeaderFlatten default true;
     property HeaderFilled: boolean read FHeaderFilled write SetHeaderFilled default true;
     property HeaderHighlightFocused: boolean read FHeaderHighlightFocused write SetHeaderHighlightFocused default false;
+    property DockSitesCanBeMinimized: boolean read FDockSitesCanBeMinimized write SetDockSitesCanBeMinimized default false;
 
     property SplitterWidth: integer read FSplitterWidth write SetSplitterWidth default 4;
     property ScaleOnResize: boolean read FScaleOnResize write SetScaleOnResize default true; // scale children when resizing a site
@@ -698,8 +779,14 @@
 
 var
   DockMaster: TAnchorDockMaster = nil;
+  DockTimer: TTimer = nil;
 
+  PreferredButtonWidth:integer=-1;
+  PreferredButtonHeight:integer=-1;
+
+
 const
+  HardcodedButtonSize:integer=13;
   ADHeaderStyleNames: array[TADHeaderStyle] of string = (
     'Frame3D',
     'Line',
@@ -970,6 +1057,27 @@
   end;
 end;
 
+function CountAndReturnOnlyOneMinimizedAnchoredControls(Control: TControl; Side: TAnchorKind): TAnchorDockHostSite;
+var
+  i,Counter: Integer;
+  Neighbour: TControl;
+begin
+  Counter:=0;
+  for i:=0 to Control.AnchoredControlCount-1 do begin
+    Neighbour:=Control.AnchoredControls[i];
+    if Neighbour.Visible then
+    if Neighbour is TAnchorDockHostSite then
+    if (OppositeAnchor[Side] in Neighbour.Anchors)
+    and (Neighbour.AnchorSide[OppositeAnchor[Side]].Control=Control) then begin
+      inc(Counter);
+      result:=TAnchorDockHostSite(Neighbour);
+    end;
+  end;
+  if (Counter=1)and(result is TAnchorDockHostSite)and((result as TAnchorDockHostSite).FMinimized) then
+  else
+    result:=Nil;
+end;
+
 function NeighbourCanBeShrinked(EnlargeControl, Neighbour: TControl;
   Side: TAnchorKind): boolean;
 { returns true if Neighbour can be shrinked on the opposite side of Side
@@ -1361,6 +1469,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockSettings.SetDockSitecCanBeMinimized(AValue: boolean);
+begin
+  if FDockSitecCanBeMinimized=AValue then Exit;
+  FDockSitecCanBeMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockSettings.Assign(Source: TAnchorDockSettings);
 begin
   FAllowDragging := Source.FAllowDragging;
@@ -1381,6 +1496,7 @@
   FShowHeaderCaption := Source.FShowHeaderCaption;
   FSplitterWidth := Source.FSplitterWidth;
   FHeaderHighlightFocused:=Source.FHeaderHighlightFocused;
+  FDockSitecCanBeMinimized:=Source.FDockSitecCanBeMinimized;
 end;
 
 procedure TAnchorDockSettings.IncreaseChangeStamp;
@@ -1407,6 +1523,7 @@
   HeaderFlatten:=Config.GetValue('HeaderFlatten',true);
   HeaderFilled:=Config.GetValue('HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue('HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue('DockSitecCanBeMinimized',False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1429,6 +1546,7 @@
   Config.SetDeleteValue(Path+'HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue(Path+'HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue(Path+'HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue(Path+'DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
 end;
 
 procedure TAnchorDockSettings.SaveToConfig(Config: TConfigStorage);
@@ -1450,6 +1568,7 @@
   Config.SetDeleteValue('HeaderFlatten',HeaderFlatten,true);
   Config.SetDeleteValue('HeaderFilled',HeaderFilled,true);
   Config.SetDeleteValue('HeaderHighlightFocused',HeaderHighlightFocused,False);
+  Config.SetDeleteValue('DockSitecCanBeMinimized',DockSitesCanBeMinimized,False);
   Config.UndoAppendBasePath;
 end;
 
@@ -1472,6 +1591,7 @@
       and (HeaderFlatten=Settings.HeaderFlatten)
       and (HeaderFilled=Settings.HeaderFilled)
       and (HeaderHighlightFocused=Settings.HeaderHighlightFocused)
+      and (DockSitesCanBeMinimized=Settings.DockSitesCanBeMinimized)
       ;
 end;
 
@@ -1494,6 +1614,7 @@
   HeaderFlatten:=Config.GetValue(Path+'HeaderFlatten',true);
   HeaderFilled:=Config.GetValue(Path+'HeaderFilled',true);
   HeaderHighlightFocused:=Config.GetValue(Path+'HeaderHighlightFocused',False);
+  DockSitesCanBeMinimized:=Config.GetValue(Path+'DockSitecCanBeMinimized',False);
 end;
 
 { TAnchorDockMaster }
@@ -2021,6 +2142,8 @@
     aHostSite:=TAnchorDockHostSite(Site);
     aHostSite.Header.HeaderPosition:=ANode.HeaderPosition;
     aHostSite.DockRestoreBounds:=NewBounds;
+    //aHostSite.FMinimized:=ANode.Minimized;
+    //we update aHostSite.FMinimized in TAnchorDockMaster.SetMinimizedState
     if (ANode.NodeType<>adltnPages) and (aHostSite.Pages<>nil) then
       aHostSite.FreePages;
   end;
@@ -2040,6 +2163,25 @@
   fTreeNameToDocker[Node.Name]:=Result;
 end;
 
+procedure TAnchorDockMaster.SetNodeMinimizedState(ANode: TAnchorDockLayoutTreeNode);
+var
+  HostSite:TAnchorDockHostSite;
+  i:integer;
+begin
+  HostSite:=GetNodeSite(ANode);
+  if Assigned(HostSite) then
+    if HostSite.FMinimized<>ANode.Minimized then
+      Application.QueueAsyncCall(@HostSite.AsyncMinimizeSite,0);
+      //HostSite.MinimizeSite;
+  for i:=0 to ANode.Count-1 do
+    SetnodeMinimizedState(ANode.Nodes[i]);
+end;
+
+procedure TAnchorDockMaster.SetMinimizedState(Tree: TAnchorDockLayoutTree);
+begin
+  SetnodeMinimizedState(Tree.Root);
+end;
+
 function TAnchorDockMaster.RestoreLayout(Tree: TAnchorDockLayoutTree;
   Scale: boolean): boolean;
 
@@ -2193,7 +2335,7 @@
       try
         SetupSite(Site,ANode,AParent);
         Site.FSiteType:=adhstPages;
-        Site.Header.Parent:=nil;
+        //Site.Header.Parent:=nil;
         if Site.Pages=nil then
           Site.CreatePages;
         for i:=0 to ANode.Count-1 do begin
@@ -2358,7 +2500,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -2368,6 +2510,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -2422,11 +2565,54 @@
   OptionsChanged;
 end;
 
+procedure TAnchorDockMaster.StartHideOverlappingTimer;
+begin
+  if not DockTimer.Enabled then begin
+    DockTimer.Interval:=HideOverlappingFormByMouseLoseTime;
+    DockTimer.OnTimer:=@HideOverlappingForm;
+    DockTimer.Enabled:=true;
+  end;
+end;
+
+procedure TAnchorDockMaster.StopHideOverlappingTimer;
+begin
+  DockTimer.Enabled:=False;
+  DockTimer.Interval:=0;
+  DockTimer.OnTimer:=nil;
+end;
+
+function IsParentControl(aParent, aControl: TControl): boolean;
+begin
+  while (aControl <> nil) and (aControl.Parent <> nil) do
+  begin
+    if (aControl=aParent) then
+      exit(true);
+    aControl := aControl.Parent;
+  end;
+  result:=aControl=aParent;
+end;
+
+
 procedure TAnchorDockMaster.OnIdle(Sender: TObject; var Done: Boolean);
+var
+  MousePos: TPoint;
+  Bounds:Trect;
 begin
   if Done then ;
-  IdleConnected:=false;
   Restoring:=false;
+  if FOverlappingForm=nil then
+    IdleConnected:=false
+  else begin
+    GetCursorPos(MousePos);
+    Bounds.TopLeft:=FOverlappingForm.ClientToScreen(point(0,0));
+    Bounds.BottomRight:=FOverlappingForm.ClientToScreen(point(FOverlappingForm.Width,FOverlappingForm.Height));
+    if not IsParentControl(FOverlappingForm, GetCaptureControl) then begin
+      if not PtInRect(Bounds,MousePos) then
+          StartHideOverlappingTimer
+        else
+          StopHideOverlappingTimer;
+    end;
+  end;
 end;
 
 procedure TAnchorDockMaster.AsyncSimplify(Data: PtrInt);
@@ -2514,6 +2700,18 @@
   InvalidateHeaders;
 end;
 
+procedure TAnchorDockMaster.SetDockSitesCanBeMinimized(AValue: boolean);
+var
+  i:integer;
+  Site: TAnchorDockHostSite;
+begin
+  if FDockSitesCanBeMinimized=AValue then Exit;
+  FDockSitesCanBeMinimized:=AValue;
+  UpdateHeaders;
+  InvalidateHeaders;
+  EnableAllAutoSizing;
+  OptionsChanged;
+end;
 procedure TAnchorDockMaster.SetScaleOnResize(AValue: boolean);
 begin
   if FScaleOnResize=AValue then Exit;
@@ -2598,6 +2796,9 @@
     if (Site.Header<>nil) then begin
       DisableControlAutoSizing(Site);
       Site.UpdateHeaderShowing;
+      if Site.fminimized then
+        if not AValue then
+          site.MinimizeSite;
     end;
   end;
   EnableAllAutoSizing;
@@ -2668,6 +2869,20 @@
     EnableAllAutoSizing;
 end;
 
+procedure TAnchorDockMaster.ShowOverlappingForm;
+begin
+  FOverlappingForm.Show;
+  IdleConnected:=true;
+end;
+
+procedure TAnchorDockMaster.HideOverlappingForm(Sender: TObject);
+begin
+  StopHideOverlappingTimer;
+  FOverlappingForm.Hide;
+  FOverlappingForm.AnchorDockHostSite.HideMinimizedControl;
+  IdleConnected:=false;
+end;
+
 constructor TAnchorDockMaster.Create(AOwner: TComponent);
 begin
   inherited Create(AOwner);
@@ -2698,14 +2913,14 @@
   FPageClass:=TAnchorDockPage;
   FRestoreLayouts:=TAnchorDockRestoreLayouts.Create;
   FHeaderHighlightFocused:=false;
+  FDockSitesCanBeMinimized:=false;
+  FOverlappingForm:=nil;
 end;
 
 destructor TAnchorDockMaster.Destroy;
 var
   AControl: TControl;
-  {$IFDEF VerboseAnchorDocking}
-  i: Integer;
-  {$ENDIF}
+  i, j: Integer;
 begin
   QueueSimplify:=false;
   FreeAndNil(FRestoreLayouts);
@@ -2727,6 +2942,12 @@
     debugln(['TAnchorDockMaster.Destroy ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   end;
   {$ENDIF}
+  for i:=0 to ComponentCount-1 do begin
+    for j:=0 to ComponentCount-1 do begin
+      if i<>j then
+        TControl(Components[i]).RemoveAllHandlersOfObject(TControl(Components[j]));
+  end;
+  end;
   inherited Destroy;
 end;
 
@@ -2914,6 +3135,7 @@
       raise Exception.Create('TAnchorDockMaster.MakeDockable '+Format(
         adrsNotSupportedHasParent, [DbgSName(AControl), DbgSName(AControl)]));
     end;
+    site.UpdateHeaderShowing;
     if (Site<>nil) and Show then
       MakeVisible(Site,BringToFront);
   finally
@@ -3018,7 +3240,8 @@
   i:=Screen.CustomFormCount-1;
   while i>=0 do begin
     AForm:=GetParentForm(Screen.CustomForms[i]);
-    AForm.Hide;
+    if Assigned(AForm)then
+      AForm.Hide;
     i:=Min(i,Screen.CustomFormCount)-1;
   end;
 
@@ -3062,8 +3285,11 @@
   end;
 end;
 
-function GetParentFormOrDockPanel(Control: TControl): TCustomForm;
+function GetParentFormOrDockPanel(Control: TControl; TopForm:Boolean=true): TCustomForm;
+var
+  oldControl: TControl;
 begin
+  oldControl:=Control;
   while (Control <> nil) and (Control.Parent <> nil) do
   begin
     if (Control is TAnchorDockPanel) then
@@ -3076,6 +3302,18 @@
     Result := TCustomForm(Control)
   else
     Result := nil;
+  if not TopForm then begin
+    if Control is TAnchorDockPanel then
+      exit;
+    Control:=oldControl;
+    while (Control <> nil) and (Control.Parent <> nil) do
+    begin
+      Control := Control.Parent;
+      if (Control is TCustomForm) then
+        Break;
+    end;
+    Result := TCustomForm(Control);
+  end;
 end;
 
 procedure TAnchorDockMaster.SaveMainLayoutToTree(LayoutTree: TAnchorDockLayoutTree);
@@ -3088,12 +3326,12 @@
   AFormOrDockPanel: TWinControl;
   VisibleControls: TStringList;
 
-  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean);
+  procedure SaveFormOrDockPanel(theFormOrDockPanel: TWinControl; SaveChildren: boolean; AMinimized:boolean);
   begin
     // custom dock site
     LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
     LayoutNode.NodeType:=adltnCustomSite;
-    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel);
+    LayoutNode.Assign(theFormOrDockPanel,theFormOrDockPanel is TAnchorDockPanel,AMinimized);
     // can have one normal dock site
     if SaveChildren then
     begin
@@ -3124,7 +3362,7 @@
       debugln(['TAnchorDockMaster.SaveMainLayoutToTree AForm=',DbgSName(AFormOrDockPanel)]);
       DebugWriteChildAnchors(AFormOrDockPanel,true,true);
       if AFormOrDockPanel is TAnchorDockPanel then begin
-        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),{false}true);
+        SaveFormOrDockPanel(GetParentFormOrDockPanel(AFormOrDockPanel),true,false);
         //LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         //TAnchorDockPanel(AFormOrDockPanel).SaveLayout(LayoutTree,LayoutNode);
       end else if AFormOrDockPanel is TAnchorDockHostSite then begin
@@ -3132,12 +3370,12 @@
         LayoutNode:=LayoutTree.NewNode(LayoutTree.Root);
         Site.SaveLayout(LayoutTree,LayoutNode);
       end else if IsCustomSite(AFormOrDockPanel) then begin
-        SaveFormOrDockPanel(AFormOrDockPanel,true);
+        SaveFormOrDockPanel(AFormOrDockPanel,true,false);
       end else
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    LayoutTree.Root.Simplify(VisibleControls);
+    LayoutTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;
@@ -3157,7 +3395,7 @@
     (AControl as TAnchorDockPanel).SaveLayout(LayoutTree,LayoutTree.Root);
   end else if IsCustomSite(AControl) then begin
     LayoutTree.Root.NodeType:=adltnCustomSite;
-    LayoutTree.Root.Assign(AControl);
+    LayoutTree.Root.Assign(AControl,false,false);
     // can have one normal dock site
     Site:=TAnchorDockManager(AControl.DockManager).GetChildSite;
     if Site<>nil then begin
@@ -3252,7 +3490,7 @@
       debugln(ControlNames.Text);
       {$ENDIF}
       // if some forms/controls could not be created the layout needs to be adapted
-      Tree.Root.Simplify(ControlNames);
+      Tree.Root.Simplify(ControlNames,false);
 
       // reuse existing sites to reduce flickering
       MapTreeToControls(Tree);
@@ -3262,6 +3500,7 @@
 
       // create sites, move controls
       RestoreLayout(Tree,Scale);
+      SetMinimizedState(Tree);
     finally
       EndUpdate;
     end;
@@ -3323,6 +3562,7 @@
   HeaderFlatten                    := Settings.HeaderFlatten;
   HeaderFilled                     := Settings.HeaderFilled;
   HeaderHighlightFocused           := Settings.HeaderHighlightFocused;
+  DockSitesCanBeMinimized          := Settings.DockSitesCanBeMinimized;
 end;
 
 procedure TAnchorDockMaster.SaveSettings(Settings: TAnchorDockSettings);
@@ -3343,6 +3583,7 @@
   Settings.HeaderFlatten:=HeaderFlatten;
   Settings.HeaderFilled:=HeaderFilled;
   Settings.HeaderHighlightFocused:=HeaderHighlightFocused;
+  Settings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized;
 end;
 
 function TAnchorDockMaster.SettingsAreEqual(Settings: TAnchorDockSettings
@@ -3436,8 +3677,11 @@
   if fUpdateCount<=0 then
     RaiseGDBException('');
   dec(fUpdateCount);
-  if fUpdateCount=0 then
+  if fUpdateCount=0 then begin
     SimplifyPendingLayouts;
+    UpdateHeaders;
+    InvalidateHeaders;
+  end;
 end;
 
 function TAnchorDockMaster.IsReleasing(AControl: TControl): Boolean;
@@ -3664,6 +3908,24 @@
   LUIncreaseChangeStamp64(FOptionsChangeStamp);
 end;
 
+procedure TAnchorDockMaster.UpdateHeaders;
+var
+  i: Integer;
+  AControl: TControl;
+  AHostSite: TAnchorDockHostSite;
+begin
+    for i:=0 to ControlCount-1 do begin
+      AControl:=Controls[i];
+      if not DockedControlIsVisible(AControl) then continue;
+      while Assigned(AControl) do
+      begin
+        if AControl is TAnchorDockHostSite then
+          TAnchorDockHostSite(AControl).UpdateHeaderShowing;
+        AControl:=AControl.parent;
+      end;
+    end;
+end;
+
 { TAnchorDockHostSite }
 
 procedure TAnchorDockHostSite.SetHeaderSide(const AValue: TAnchorKind);
@@ -3680,6 +3942,7 @@
     AControl:=TControl(Sender);
     if not (csDestroying in ComponentState) then begin
       if (not AControl.Visible)
+      and (not FMinimized)
       and (not ((AControl is TAnchorDockHeader)
                or (AControl is TAnchorDockSplitter)
                or (AControl is TAnchorDockHostSite)))
@@ -4119,6 +4382,8 @@
 end;
 
 procedure TAnchorDockHostSite.FreePages;
+var
+  i:Integer;
 begin
   FreeAndNil(FPages);
 end;
@@ -4233,6 +4498,14 @@
         akRight: NewBounds.Right:=AControl.Left+AControl.Width;
         akBottom: NewBounds.Bottom:=AControl.Top+AControl.Height;
         end;
+        if (sibling is TAnchorDockHostSite) then
+        if (sibling as TAnchorDockHostSite).FMinimized then begin
+          (sibling as TAnchorDockHostSite).FMinimized:=false;
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Parent:=(sibling as TAnchorDockHostSite);
+          (sibling as TAnchorDockHostSite).FMinimizedControl.Visible:=True;
+          (sibling as TAnchorDockHostSite).FMinimizedControl:=nil;
+          (sibling as TAnchorDockHostSite).UpdateHeaderAlign;
+        end;
         Sibling.BoundsRect:=NewBounds;
       end;
     end;
@@ -4306,6 +4579,13 @@
       FSiteType:=adhstOneControl;
       OnlySiteLeft.Align:=alClient;
       Header.Parent:=Self;
+      if OnlySiteLeft.FMinimized then begin
+        OnlySiteLeft.FMinimized:=false;
+        OnlySiteLeft.FMinimizedControl.Parent:=OnlySiteLeft;
+        OnlySiteLeft.FMinimizedControl.Visible:=True;
+        OnlySiteLeft.FMinimizedControl:=nil;
+        UpdateHeaderAlign;
+      end;
       UpdateHeaderAlign;
 
       //debugln(['TAnchorDockHostSite.RemoveControlFromLayout.ConvertToOneControlType AFTER CONVERT "',Caption,'" to onecontrol OnlySiteLeft="',OnlySiteLeft.Caption,'"']);
@@ -4465,7 +4745,7 @@
     debugln(['TAnchorDockHostSite.Simplify ',DbgSName(Self),' ',DbgSName(AControl)]);
     if AControl is TAnchorDockHostSite then
       SimplifyOneControl
-    else if (AControl=nil) or (csDestroying in AControl.ComponentState) then
+    else if ((AControl=nil) or (csDestroying in AControl.ComponentState)) then
       DockMaster.NeedFree(Self);
   end;
 end;
@@ -4577,7 +4857,8 @@
     Result:=Controls[i];
     if Result.Owner<>Self then exit;
   end;
-  Result:=nil;
+  result:=FMinimizedControl;
+  //Result:=nil;
 end;
 
 function TAnchorDockHostSite.GetSiteCount: integer;
@@ -5165,6 +5446,125 @@
   Result:=Check(Self);
 end;
 
+function CheckOposite(Side:TAnchorKind;AControl: TControl;out Splitter: TAnchorDockSplitter; out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=GetDockSplitter(AControl,Side,Splitter);
+  if result then begin
+    if CountAnchoredControls(Splitter,OppositeAnchor[Side])=1 then begin
+      SplitterAnchorKind:=Side;
+      exit;
+    end;
+  end;
+  result:=false
+end;
+
+function FindNearestSpliter(AControl: TControl;out Splitter: TAnchorDockSplitter;out SplitterAnchorKind:TAnchorKind):boolean;
+begin
+  result:=CheckOposite(akTop,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akRight,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akBottom,AControl,Splitter,SplitterAnchorKind);
+  if result then exit;
+  result:=CheckOposite(akLeft,AControl,Splitter,SplitterAnchorKind);
+end;
+
+function TAnchorDockHostSite.CanBeMinimized(out Splitter: TAnchorDockSplitter;
+                                            out SplitterAnchorKind:TAnchorKind):boolean;
+var
+  //AControl: TControl;
+  OpositeDockHostSite:TAnchorDockHostSite;
+  OpositeSplitter: TAnchorDockSplitter;
+begin
+  result:=false;
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    OpositeDockHostSite:=CountAndReturnOnlyOneMinimizedAnchoredControls(Splitter,SplitterAnchorKind);
+    if (Splitter.Enabled and (OpositeDockHostSite=nil)) then begin
+      result:=true;
+      if CheckOposite(OppositeAnchorKind[SplitterAnchorKind],self,OpositeSplitter,SplitterAnchorKind) then
+      if Assigned(OpositeSplitter) then
+      if not OpositeSplitter.Enabled then
+        result:=false;
+    end;
+  end;
+end;
+
+procedure TAnchorDockHostSite.MinimizeSite;
+begin
+  //Application.QueueAsyncCall(@AsyncMinimizeSite,0);
+  AsyncMinimizeSite(0);
+end;
+
+procedure TAnchorDockHostSite.AsyncMinimizeSite(Data: PtrInt);
+var
+  AControl: TControl;
+  //OpositeDockHostSite:TAnchorDockHostSite;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  //SpliterPercentPosition:Single;
+begin
+  fMinimization:=true;
+  debugln(['TAnchorDockHostSite.MinimizeSite ',DbgSName(Self),' SiteType=',dbgs(SiteType)]);
+  if FMinimized then
+    AControl:=FMinimizedControl
+  else
+    AControl:=GetOneControl;
+  if CanBeMinimized(Splitter,SplitterAnchorKind) or FMinimized then begin
+    FMinimized:=not FMinimized;
+    if FMinimized then begin
+      FMinimizedControl:=AControl;
+      AControl.Visible:=False;
+      AControl.Parent:=nil;
+      //self.DoDockOver(); OnDockOver;
+    end else begin
+      AControl.Parent:=self;
+      AControl.Visible:=True;
+      FMinimizedControl:=nil;
+    end;
+    Splitter.Enabled:=AControl.Visible;
+    UpdateHeaderAlign;
+    dockmaster.UpdateHeaders;
+    dockmaster.InvalidateHeaders;
+    Splitter.SetBoundsPercentually;
+  end;
+  fMinimization:=false;
+end;
+
+procedure TAnchorDockHostSite.ShowMinimizedControl;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  SpliterRect,OverlappingFormRect:TRect;
+begin
+  if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+    SpliterRect:=Splitter.GetSpliterBoundsWithUnminimizedDockSites;
+    OverlappingFormRect:=BoundsRect;
+    case SplitterAnchorKind of
+         akTop:OverlappingFormRect.Top:=SpliterRect.Bottom;
+        akLeft:OverlappingFormRect.Left:=SpliterRect.Right;
+       akRight:OverlappingFormRect.Right:=SpliterRect.Left;
+      akBottom:OverlappingFormRect.Bottom:=SpliterRect.Top;
+    end;
+    DockMaster.FOverlappingForm:=TAnchorDockOverlappingForm.CreateNew(self);
+    DockMaster.FOverlappingForm.BoundsRect:=OverlappingFormRect;
+    DockMaster.FOverlappingForm.Parent:=GetParentFormOrDockPanel(self,false);
+    DockMaster.FOverlappingForm.AnchorDockHostSite:=self;
+    header.Parent:=DockMaster.FOverlappingForm;
+    FMinimizedControl.Parent:=DockMaster.FOverlappingForm.Panel;
+    FMinimizedControl.Show;
+    DockMaster.ShowOverlappingForm;
+  end;
+end;
+
+procedure TAnchorDockHostSite.HideMinimizedControl;
+begin
+   FMinimizedControl.Hide;
+   header.Parent:=self;
+   header.UpdateHeaderControls;
+   FMinimizedControl.Parent:=nil;
+   FreeAndNil(DockMaster.FOverlappingForm);
+end;
+
 function TAnchorDockHostSite.CloseSite: boolean;
 var
   AControl: TControl;
@@ -5281,21 +5681,24 @@
 begin
   if csDestroying in ComponentState then exit;
   NewCaption:='';
-  for i:=0 to ControlCount-1 do begin
-    Child:=Controls[i];
-    if Child=Exclude then continue;
-    if (Child.HostDockSite=Self) or (Child is TAnchorDockHostSite)
-    or (Child is TAnchorDockPageControl) then begin
-      if NewCaption<>'' then
-        NewCaption:=NewCaption+',';
-      NewCaption:=NewCaption+Child.Caption;
+  if FMinimized then
+    NewCaption:=FMinimizedControl.Caption
+  else
+    for i:=0 to ControlCount-1 do begin
+      Child:=Controls[i];
+      if Child=Exclude then continue;
+      if (Child.HostDockSite=Self) or (Child is TAnchorDockHostSite)
+      or (Child is TAnchorDockPageControl) then begin
+        if NewCaption<>'' then
+          NewCaption:=NewCaption+',';
+        NewCaption:=NewCaption+Child.Caption;
+      end;
     end;
-  end;
   OldCaption:=Caption;
   Caption:=NewCaption;
   //debugln(['TAnchorDockHostSite.UpdateDockCaption Caption="',Caption,'" NewCaption="',NewCaption,'" HasParent=',Parent<>nil,' ',DbgSName(Header)]);
-  if ((Parent=nil) and DockMaster.HideHeaderCaptionFloatingControl)
-  or (not DockMaster.ShowHeaderCaption) then
+  if {((Parent=nil) and DockMaster.HideHeaderCaptionFloatingControl)
+  or (not DockMaster.ShowHeaderCaption)}false then
     Header.Caption:=''
   else
     Header.Caption:=Caption;
@@ -5306,9 +5709,8 @@
     if Parent is TAnchorDockPage then
       TAnchorDockPage(Parent).UpdateDockCaption;
   end;
-
   // do not show close button for mainform
-  Header.CloseButton.Visible:=not IsParentOf(Application.MainForm);
+  Header.CloseButton.Visible:=(not IsParentOf(Application.MainForm));
 end;
 
 procedure TAnchorDockHostSite.GetSiteInfo(Client: TControl;
@@ -5339,7 +5741,8 @@
   end;
 
   CanDock:=(Client is TAnchorDockHostSite)
-           and not DockMaster.AutoFreedIfControlIsRemoved(Self,Client);
+           and not DockMaster.AutoFreedIfControlIsRemoved(Self,Client)
+           and not FMinimized;
   //debugln(['TAnchorDockHostSite.GetSiteInfo ',DbgSName(Self),' ',dbgs(BoundsRect),' ',Caption,' CanDock=',CanDock,' PtIn=',PtInRect(InfluenceRect,MousePos)]);
 
   if Assigned(OnGetSiteInfo) then
@@ -5362,9 +5765,20 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderAlign;
+var
+  NeededHeaderPosition:TADLHeaderPosition;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  case Header.HeaderPosition of
+  if FMinimized then begin
+    if FindNearestSpliter(self,Splitter,SplitterAnchorKind) then begin
+      NeededHeaderPosition:=OppositeAnchorKind2TADLHeaderPosition[SplitterAnchorKind];
+    end else
+      NeededHeaderPosition:=Header.HeaderPosition;
+  end else
+    NeededHeaderPosition:=Header.HeaderPosition;
+  case NeededHeaderPosition of
   adlhpAuto:
     if Header.Align in [alLeft,alRight] then begin
       if (ClientHeight>0)
@@ -5388,10 +5802,16 @@
 end;
 
 procedure TAnchorDockHostSite.UpdateHeaderShowing;
+var
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
 begin
   if Header=nil then exit;
-  if HeaderNeedsShowing then
-    Header.Parent:=Self
+  if HeaderNeedsShowing then begin
+    Header.Parent:=Self;
+    Header.MinimizeButton.Visible:=(DockMaster.DockSitesCanBeMinimized and CanBeMinimized(Splitter,SplitterAnchorKind))or FMinimized;
+    Header.MinimizeButton.Parent:=Header;
+  end
   else
     Header.Parent:=nil;
 end;
@@ -5415,6 +5835,31 @@
   Result:=(fUpdateLayout>0) or (csDestroying in ComponentState);
 end;
 
+function AcceptAlign(Site:TAnchorDockHostSite; AlignCandidate:TAlign):TAlign;
+var
+  i:integer;
+  Splitter: TAnchorDockSplitter;
+  SplitterAnchorKind:TAnchorKind;
+  MinimizedSiteAlign:TAlign;
+begin
+  for i:=0 to Site.ControlCount-1 do
+    if Site.Controls[i] is TAnchorDockHostSite then
+      if (Site.Controls[i] as TAnchorDockHostSite).FMinimized then begin
+        if FindNearestSpliter(Site.Controls[i] as TAnchorDockHostSite,Splitter,SplitterAnchorKind) then begin
+          MinimizedSiteAlign:=OppositeAnchorKind2Align[SplitterAnchorKind];
+          if AlignCandidate=MinimizedSiteAlign then
+            exit(alNone);
+        end
+      end;
+  result:=AlignCandidate;
+end;
+
+function TAnchorDockHostSite.GetDockEdge(const MousePos: TPoint): TAlign;
+begin
+  result:=inherited;
+  result:=AcceptAlign(self,result);
+end;
+
 procedure TAnchorDockHostSite.SaveLayout(
   LayoutTree: TAnchorDockLayoutTree; LayoutNode: TAnchorDockLayoutTreeNode);
 var
@@ -5432,7 +5877,7 @@
   if (SiteType=adhstOneControl) and (OneControl<>nil)
   and (not (OneControl is TAnchorDockHostSite)) then begin
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.Name:=OneControl.Name;
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if (SiteType in [adhstLayout,adhstOneControl]) then begin
@@ -5450,7 +5895,7 @@
         Splitter.SaveLayout(ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else if SiteType=adhstPages then begin
     LayoutNode.NodeType:=adltnPages;
@@ -5461,7 +5906,7 @@
         Site.SaveLayout(LayoutTree,ChildNode);
       end;
     end;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,FMinimized);
     LayoutNode.HeaderPosition:=Header.HeaderPosition;
   end else
     LayoutNode.NodeType:=adltnNone;
@@ -5476,6 +5921,9 @@
 constructor TAnchorDockHostSite.CreateNew(AOwner: TComponent; Num: Integer);
 begin
   inherited CreateNew(AOwner,Num);
+  FMinimized:=false;
+  fMinimization:=false;
+  FMinimizedControl:=Nil;
   Visible:=false;
   FHeaderSide:=akTop;
   FHeader:=DockMaster.HeaderClass.Create(Self);
@@ -5490,13 +5938,13 @@
 end;
 
 destructor TAnchorDockHostSite.Destroy;
-//var i: Integer;
+var i: Integer;
 begin
-  //debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
-  {for i:=0 to ComponentCount-1 do
+  debugln(['TAnchorDockHostSite.Destroy ',DbgSName(Self),' Caption="',Caption,'" Self=',dbgs(Pointer(Self)),' ComponentCount=',ComponentCount,' ControlCount=',ControlCount]);
+  for i:=0 to ComponentCount-1 do
     debugln(['TAnchorDockHostSite.Destroy Component ',i,'/',ComponentCount,' ',DbgSName(Components[i])]);
   for i:=0 to ControlCount-1 do
-    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);}
+    debugln(['TAnchorDockHostSite.Destroy Control ',i,'/',ControlCount,' ',DbgSName(Controls[i])]);
   FreePages;
   inherited Destroy;
 end;
@@ -5562,13 +6010,34 @@
 end;
 
 procedure TAnchorDockHeader.CloseButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
 begin
-  if Parent is TAnchorDockHostSite then begin
-    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(Parent),true);
-    TAnchorDockHostSite(Parent).CloseSite;
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
   end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    DockMaster.RestoreLayouts.Add(DockMaster.CreateRestoreLayout(HeaderParent),true);
+    HeaderParent.CloseSite;
+  end;
 end;
 
+procedure TAnchorDockHeader.MinimizeButtonClick(Sender: TObject);
+var
+  HeaderParent:TAnchorDockHostSite;
+begin
+  TWinControl(HeaderParent):=Parent;
+  if HeaderParent=TWinControl(DockMaster.FOverlappingForm) then begin
+    HeaderParent:=DockMaster.FOverlappingForm.AnchorDockHostSite;
+    HeaderParent.HideMinimizedControl;
+  end;
+  if HeaderParent is TAnchorDockHostSite then begin
+    HeaderParent.MinimizeSite;
+  end;
+end;
+
 procedure TAnchorDockHeader.HeaderPositionItemClick(Sender: TObject);
 var
   Item: TMenuItem;
@@ -5635,11 +6104,18 @@
 
   if CloseButton.IsControlVisible and (CloseButton.Parent=Self) then begin
     if Align in [alLeft,alRight] then
-      r.Top:=CloseButton.Top+CloseButton.Height+1
+      r.Top:=CloseButton.Top+CloseButton.Height+ButtonBorderSpacingAround
     else
-      r.Right:=CloseButton.Left-1;
+      r.Right:=CloseButton.Left-ButtonBorderSpacingAround;
   end;
 
+  if MinimizeButton.IsControlVisible and (MinimizeButton.Parent=Self) then begin
+    if Align in [alLeft,alRight] then
+      r.Top:=MinimizeButton.Top+MinimizeButton.Height+ButtonBorderSpacingAround
+    else
+      r.Right:=MinimizeButton.Left-ButtonBorderSpacingAround;
+  end;
+
   // caption
   if Caption<>'' then begin
     if fFocused and DockMaster.HeaderHighlightFocused and NeedHighlightText then
@@ -5728,26 +6204,127 @@
     end else begin
       PreferredHeight:=Max(NeededHeight,PreferredHeight);
     end;
+  end else begin
+    NeededHeight:=CloseButton.Height;
+    if Align in [alLeft,alRight] then begin
+      PreferredWidth:=Max(NeededHeight,PreferredWidth);
+    end else begin
+      PreferredHeight:=Max(NeededHeight,PreferredHeight);
   end;
+  end;
 end;
 
 procedure TAnchorDockHeader.MouseDown(Button: TMouseButton; Shift: TShiftState;
   X, Y: Integer);
+var
+  SiteMinimized:Boolean;
 begin
   inherited MouseDown(Button, Shift, X, Y);
-  if (Button=mbLeft) and DockMaster.AllowDragging then
-    DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
+  SiteMinimized:=False;
+  fUseTimer:=false;
+  StopMouseNoMoveTimer;
+  if Parent is TAnchorDockHostSite then
+    SiteMinimized:=(Parent as TAnchorDockHostSite).FMinimized;
+  if SiteMinimized then begin
+    DoMouseNoMoveTimer(nil);
+  end else
+    begin
+      if parent<>nil then
+        if DockMaster.FOverlappingForm<>nil then
+          //if parent=DockMaster.FOverlappingForm.Panel then
+            DockMaster.HideOverlappingForm(nil);
+      if (Button=mbLeft) and (DockMaster.AllowDragging) and (DockMaster.FOverlappingForm=nil) then
+        DragManager.DragStart(Parent,false,DockMaster.DragTreshold);
+    end;
 end;
 
+procedure  TAnchorDockHeader.MouseMove(Shift: TShiftState; X,Y: Integer);
+begin
+  inherited MouseMove(Shift, X, Y);
+  if parent<>nil then
+    if parent is TAnchorDockHostSite then
+      if (parent as TAnchorDockHostSite).FMinimized then
+        if DockMaster.FOverlappingForm=nil then
+          if FMouseTimeStartX=EmptyMouseTimeStartX then
+            StartMouseNoMoveTimer(X, Y)
+          else begin
+            if (abs(FMouseTimeStartX-X)>MouseNoMoveDelta)or(abs(FMouseTimeStartY-Y)>MouseNoMoveDelta)then
+            StopMouseNoMoveTimer;
+          end;
+  if (parent is TAnchorDockHostSite)and(DockMaster.FOverlappingForm=nil)then
+    fUseTimer:=true;
+end;
+
+procedure TAnchorDockHeader.MouseLeave;
+begin
+  inherited;
+  StopMouseNoMoveTimer;
+end;
+
+procedure TAnchorDockHeader.StartMouseNoMoveTimer(X, Y: Integer);
+begin
+  if fUseTimer then begin
+    if DockTimer.Enabled then DockTimer.Enabled:=false;
+    DockTimer.Interval:=MouseNoMoveTime;
+    DockTimer.OnTimer:=@DoMouseNoMoveTimer;
+    DockTimer.Enabled:=true;
+  end;
+end;
+
+procedure TAnchorDockHeader.StopMouseNoMoveTimer;
+begin
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  DockTimer.OnTimer:=nil;
+  DockTimer.Enabled:=false;
+end;
+
+procedure TAnchorDockHeader.DoMouseNoMoveTimer(Sender: TObject);
+begin
+  StopMouseNoMoveTimer;
+  //if fUseTimer then
+    if parent<>nil then
+      if parent is TAnchorDockHostSite then
+        if (parent as TAnchorDockHostSite).FMinimized then
+          (parent as TAnchorDockHostSite).ShowMinimizedControl;
+end;
+
 procedure TAnchorDockHeader.UpdateHeaderControls;
 begin
   if Align in [alLeft,alRight] then begin
-    if CloseButton<>nil then
-      CloseButton.Align:=alTop;
+    if CloseButton<>nil then begin
+      //MinimizeButton.Align:=alTop;
+      //CloseButton.Align:=alTop;
+      CloseButton.AnchorSide[akRight].Side := asrCenter;
+      CloseButton.AnchorSide[akRight].Control := self;
+      CloseButton.AnchorSide[akTop].Side := asrTop;
+      CloseButton.AnchorSide[akTop].Control := self;
+      CloseButton.Anchors := CloseButton.Anchors + [akTop] + [akRight];
+
+      MinimizeButton.AnchorSide[akRight].Side := asrCenter;
+      MinimizeButton.AnchorSide[akRight].Control := CloseButton;
+      MinimizeButton.AnchorSide[akTop].Side := asrBottom;
+      MinimizeButton.AnchorSide[akTop].Control := CloseButton;
+      MinimizeButton.Anchors := MinimizeButton.Anchors + [akTop] + [akRight];
+    end;
   end else begin
-    if CloseButton<>nil then
-      CloseButton.Align:=alRight;
+    if CloseButton<>nil then begin
+      //MinimizeButton.Align:=alRight;
+      //CloseButton.Align:=alRight;
+      CloseButton.AnchorSide[akRight].Side := asrRight;
+      CloseButton.AnchorSide[akRight].Control := self;
+      CloseButton.AnchorSide[akTop].Side := asrCenter;
+      CloseButton.AnchorSide[akTop].Control := self;
+      CloseButton.Anchors := CloseButton.Anchors - [akLeft] + [akRight];
+
+      MinimizeButton.AnchorSide[akRight].Side := asrLeft;
+      MinimizeButton.AnchorSide[akRight].Control := CloseButton;
+      MinimizeButton.AnchorSide[akTop].Side := asrCenter;
+      MinimizeButton.AnchorSide[akTop].Control := CloseButton;
+      MinimizeButton.Anchors := MinimizeButton.Anchors - [akLeft] + [akRight];
+    end;
   end;
+  CloseButton.BorderSpacing.Around:=ButtonBorderSpacingAround;
+  MinimizeButton.BorderSpacing.Around:=ButtonBorderSpacingAround;
   //debugln(['TAnchorDockHeader.UpdateHeaderControls ',dbgs(Align),' ',dbgs(CloseButton.Align)]);
 end;
 
@@ -5787,9 +6364,9 @@
 begin
   inherited Create(TheOwner);
   FHeaderPosition:=adlhpAuto;
-  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   BevelOuter:=bvNone;
   BorderWidth:=0;
+  FCloseButton:=TAnchorDockCloseButton.Create(Self);
   with FCloseButton do begin
     Name:='CloseButton';
     Parent:=Self;
@@ -5799,11 +6376,23 @@
     OnClick:=@CloseButtonClick;
     AutoSize:=true;
   end;
+  FMinimizeButton:=TAnchorDockMinimizeButton.Create(Self);
+  with FMinimizeButton do begin
+    Name:='MinimizeButton';
+    Parent:=Self;
+    Flat:=true;
+    ShowHint:=true;
+    Hint:=adrsMinimize;
+    OnClick:=@MinimizeButtonClick;
+    AutoSize:=true;
+  end;
   Align:=alTop;
   AutoSize:=true;
   ShowHint:=true;
   PopupMenu:=DockMaster.GetPopupMenu;
   fFocused:=false;
+  FMouseTimeStartX:=EmptyMouseTimeStartX;
+  fUseTimer:=true;
 end;
 
 { TAnchorDockCloseButton }
@@ -5830,6 +6419,31 @@
   Result := ThemeServices.GetElementDetails(WindowPart);
 end;
 
+procedure SizeCorrector(var current,recomend:integer);
+begin
+  if recomend<0 then begin
+    if current>0 then
+      recomend:=current
+    else
+      current:=HardcodedButtonSize;
+  end else begin
+      if current>recomend then
+        current:=recomend
+      else begin
+        if current>0 then
+         recomend:=current
+        else
+         current:=recomend;
+      end;
+  end;
+end;
+
+procedure ButtonSizeCorrector(var w,h:integer);
+begin
+  SizeCorrector(w,PreferredButtonWidth);
+  SizeCorrector(h,PreferredButtonHeight);
+end;
+
 procedure TAnchorDockCloseButton.CalculatePreferredSize(var PreferredWidth,
   PreferredHeight: integer; WithThemeSpace: Boolean);
 begin
@@ -5837,6 +6451,7 @@
   begin
     PreferredWidth:=cx;
     PreferredHeight:=cy;
+    ButtonSizeCorrector(PreferredWidth,PreferredHeight);
     {$IF defined(LCLGtk2) or defined(Carbon)}
     inc(PreferredWidth,2);
     inc(PreferredHeight,2);
@@ -5844,6 +6459,45 @@
   end;
 end;
 
+{ TAnchorDockMinimizeButton }
+
+function TAnchorDockMinimizeButton.GetDrawDetails: TThemedElementDetails;
+
+function WindowPart: TThemedWindow;
+  begin
+    // no check states available
+    Result := twMinButtonNormal;
+    if not IsEnabled then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonDisabled{$ELSE}twMinButtonDisabled{$ENDIF}
+    else
+    if FState in [bsDown, bsExclusive] then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonPushed{$ELSE}twMinButtonPushed{$ENDIF}
+    else
+    if FState = bsHot then
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonHot{$ELSE}twMinButtonHot{$ENDIF}
+    else
+      Result := {$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF};
+  end;
+
+begin
+  Result := ThemeServices.GetElementDetails(WindowPart);
+end;
+
+procedure TAnchorDockMinimizeButton.CalculatePreferredSize(var PreferredWidth,
+  PreferredHeight: integer; WithThemeSpace: Boolean);
+begin
+  with ThemeServices.GetDetailSize(ThemeServices.GetElementDetails({$IFDEF LCLGtk2}twMDIRestoreButtonNormal{$ELSE}twMinButtonNormal{$ENDIF})) do
+  begin
+    PreferredWidth:=cx;
+    PreferredHeight:=cy;
+    ButtonSizeCorrector(PreferredWidth,PreferredHeight);
+    {$IF defined(LCLGtk2) or defined(Carbon)}
+    inc(PreferredWidth,2);
+    inc(PreferredHeight,2);
+    {$ENDIF}
+  end;
+end;
+
 { TAnchorDockManager }
 
 procedure TAnchorDockManager.SetPreferredSiteSizeAsSiteMinimum(
@@ -6213,6 +6867,9 @@
   ClientRectChanged:=(WidthDiff<>0) or (HeightDiff<>0);
   if ClientRectChanged or PreferredSiteSizeAsSiteMinimum then
     AlignChilds;
+  if ClientRectChanged then
+    if DockMaster.FOverlappingForm<>nil then
+      DockMaster.HideOverlappingForm(nil);
 end;
 
 procedure TAnchorDockManager.SaveToStream(Stream: TStream);
@@ -6287,6 +6944,11 @@
       ADockObject.DropOnControl:=Site
     else
       ADockObject.DropOnControl:=nil;
+    if Site is TAnchorDockHostSite then begin
+      ADockObject.DropAlign:=AcceptAlign(Site as TAnchorDockHostSite,ADockObject.DropAlign);
+      if ADockObject.DropAlign=alNone then
+        exit(false);
+    end;
   end;
   //debugln(['TAnchorDockManager.GetDockEdge ADockObject.DropAlign=',dbgs(ADockObject.DropAlign),' DropOnControl=',DbgSName(ADockObject.DropOnControl)]);
   Result:=true;
@@ -6505,32 +7167,58 @@
 procedure TAnchorDockSplitter.SetBoundsPercentually;
 var
   NewLeft, NewTop: Integer;
+  AControl: TControl;
+  SplitterAnchorKind:TAnchorKind;
 begin
-  if ResizeAnchor in [akLeft,akRight] then
-  begin
-    if DockParentClientSize.cx> 0 then
+  if Enabled then begin
+    if ResizeAnchor in [akLeft,akRight] then
     begin
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
-      else
-        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
-      NewTop := Top;
-      SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      if DockParentClientSize.cx> 0 then
+      begin
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+        else
+          NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+        NewTop := Top;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
+    end else
+    begin
+      if DockParentClientSize.cy> 0 then
+      begin
+        NewLeft := Left;
+        if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+          NewTop := Round(FPercentPosition*Parent.ClientHeight)
+        else
+          NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+        SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
+      end;
     end;
-  end else
-  begin
-    if DockParentClientSize.cy> 0 then
-    begin
-      NewLeft := Left;
-      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
-        NewTop := Round(FPercentPosition*Parent.ClientHeight)
-      else
-        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    if FPercentPosition < 0 then
+      UpdatePercentPosition;
+  end else begin
+    SplitterAnchorKind:=akTop;
+    AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);
+    if AControl=nil then begin SplitterAnchorKind:=akRight;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akBottom;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+    if AControl=nil then begin SplitterAnchorKind:=akLeft;AControl:=CountAndReturnOnlyOneMinimizedAnchoredControls(self,SplitterAnchorKind);end;
+
+    if AControl is TAnchorDockHostSite then begin
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Left;
+      NewTop := (AControl as TAnchorDockHostSite).Header.Height;
+      NewLeft := left;
+      NewTop := top;
+      (AControl as TAnchorDockHostSite).UpdateHeaderAlign;
+      case SplitterAnchorKind of
+        akTop: NewTop := AControl.Top+(AControl as TAnchorDockHostSite).Header.Height;
+        akBottom: NewTop := AControl.Top+AControl.Height-(AControl as TAnchorDockHostSite).Header.Height-Height;
+        akLeft: NewLeft := AControl.Left+(AControl as TAnchorDockHostSite).Header.Width;
+        akRight: NewLeft := AControl.Left+AControl.Width-(AControl as TAnchorDockHostSite).Header.Width-Width;
+      end;
       SetBoundsKeepDockBounds(NewLeft,NewTop,Width,Height);
     end;
   end;
-  if FPercentPosition < 0 then
-    UpdatePercentPosition;
 end;
 
 function TAnchorDockSplitter.SideAnchoredControlCount(Side: TAnchorKind): integer;
@@ -6560,14 +7248,47 @@
   end;
 end;
 
+function TAnchorDockSplitter.GetSpliterBoundsWithUnminimizedDockSites:TRect;
+var
+  NewLeft, NewTop: Integer;
+begin
+  if ResizeAnchor in [akLeft,akRight] then
+  begin
+    if DockParentClientSize.cx> 0 then
+    begin
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewLeft := Round(FPercentPosition*Parent.ClientWidth)
+      else
+        NewLeft := (DockBounds.Left*Parent.ClientWidth) div DockParentClientSize.cx;
+      NewTop := Top;
+    end;
+  end else
+  begin
+    if DockParentClientSize.cy> 0 then
+    begin
+      NewLeft := Left;
+      if (FPercentPosition > 0) or SameValue(FPercentPosition, 0) then
+        NewTop := Round(FPercentPosition*Parent.ClientHeight)
+      else
+        NewTop := (DockBounds.Top*Parent.ClientHeight) div DockParentClientSize.cy;
+    end;
+  end;
+  result:=Rect(NewLeft,NewTop,NewLeft+Width,NewTop+Height);
+end;
+
 procedure TAnchorDockSplitter.SaveLayout(
   LayoutNode: TAnchorDockLayoutTreeNode);
+var
+  NewLeft, NewTop: Integer;
 begin
   if ResizeAnchor in [akLeft,akRight] then
     LayoutNode.NodeType:=adltnSplitterVertical
   else
     LayoutNode.NodeType:=adltnSplitterHorizontal;
-  LayoutNode.Assign(Self);
+  LayoutNode.Assign(Self,false,false);
+  if not Enabled then begin
+    LayoutNode.BoundsRect:=GetSpliterBoundsWithUnminimizedDockSites;
+  end
 end;
 
 function TAnchorDockSplitter.HasOnlyOneSibling(Side: TAnchorKind; MinPos,
@@ -6645,7 +7366,7 @@
 begin
   inherited MouseDown(Button, Shift, X, Y);
   ATabIndex := IndexOfPageAt(X, Y);
-  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) then
+  if (Button = mbLeft) and DockMaster.AllowDragging and (ATabIndex >= 0) and (DockMaster.FOverlappingForm=nil) then
   begin
     APage:=Page[ATabIndex];
     if (APage.ControlCount>0) and (APage.Controls[0] is TAnchorDockHostSite) then
@@ -6782,6 +7503,20 @@
   PopupMenu:=DockMaster.GetPopupMenu;
 end;
 
+{ TAnchorDockOverlappingForm }
+
+constructor TAnchorDockOverlappingForm.CreateNew(AOwner: TComponent; Num: Integer = 0);
+begin
+  inherited;
+  BorderStyle:=bsNone;
+  AnchorDockHostSite:=nil;
+  Panel:=TPanel.Create(self);
+  Panel.BorderStyle:=bsSingle;
+  Panel.Align:=alClient;
+  Panel.Parent:=self;
+  Panel.Visible:=true;
+end;
+
 { TAnchorDockPage }
 
 procedure TAnchorDockPage.UpdateDockCaption(Exclude: TControl);
@@ -6835,9 +7570,11 @@
 
 initialization
   DockMaster:=TAnchorDockMaster.Create(nil);
+  DockTimer:=TTimer.Create(nil);
 
 finalization
   FreeAndNil(DockMaster);
+  FreeAndNil(DockTimer);
 
 end.
 
Index: components/anchordocking/anchordockoptionsdlg.lfm
===================================================================
--- components/anchordocking/anchordockoptionsdlg.lfm	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.lfm	(working copy)
@@ -1,11 +1,13 @@
 object AnchorDockOptionsFrame: TAnchorDockOptionsFrame
   Left = 0
-  Height = 482
+  Height = 567
   Top = 0
-  Width = 416
-  ClientHeight = 482
-  ClientWidth = 416
+  Width = 490
+  ClientHeight = 567
+  ClientWidth = 490
+  DesignTimePPI = 113
   OnClick = FrameClick
+  ParentFont = False
   TabOrder = 0
   DesignLeft = 513
   DesignTop = 189
@@ -12,14 +14,15 @@
   object DragThresholdLabel: TLabel
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
-    Left = 10
-    Height = 13
-    Top = 10
-    Width = 111
-    BorderSpacing.Left = 10
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 12
+    Width = 122
+    BorderSpacing.Left = 12
+    BorderSpacing.Top = 12
     Caption = 'DragThresholdLabel'
     ParentColor = False
+    ParentFont = False
   end
   object DragThresholdTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdLabel
@@ -27,15 +30,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 23
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 31
+    Width = 466
     Max = 20
     OnChange = DragThresholdTrackBarChange
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Right = 10
+    BorderSpacing.Right = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 1
@@ -46,12 +50,13 @@
     AnchorSideTop.Control = DragThresholdLabel
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
-    Left = 127
-    Height = 23
-    Top = 5
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 141
+    Height = 27
+    Top = 8
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 20
+    ParentFont = False
     TabOrder = 0
     Visible = False
   end
@@ -59,13 +64,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = DragThresholdTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 79
-    Width = 103
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 97
+    Width = 112
+    BorderSpacing.Top = 12
     Caption = 'SplitterWidthLabel'
     ParentColor = False
+    ParentFont = False
   end
   object SplitterWidthTrackBar: TTrackBar
     AnchorSideLeft.Control = DragThresholdTrackBar
@@ -73,14 +79,15 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 46
-    Top = 92
-    Width = 396
+    Left = 12
+    Height = 54
+    Top = 116
+    Width = 466
     Min = 1
     OnChange = SplitterWidthTrackBarChange
     Position = 1
     Anchors = [akTop, akLeft, akRight]
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 3
@@ -89,12 +96,13 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = SplitterWidthTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 142
-    Width = 160
-    BorderSpacing.Top = 4
+    Left = 12
+    Height = 23
+    Top = 175
+    Width = 169
+    BorderSpacing.Top = 5
     Caption = 'ScaleOnResizeCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 4
@@ -103,12 +111,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 24
-    Top = 166
-    Width = 149
+    Left = 12
+    Height = 23
+    Top = 198
+    Width = 160
     Caption = 'ShowHeaderCheckBox'
     OnChange = ShowHeaderCheckBoxChange
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 5
@@ -117,12 +126,13 @@
     AnchorSideLeft.Control = ScaleOnResizeCheckBox
     AnchorSideTop.Control = ShowHeaderCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 190
-    Width = 191
-    BorderSpacing.Left = 15
+    Left = 30
+    Height = 23
+    Top = 221
+    Width = 208
+    BorderSpacing.Left = 18
     Caption = 'ShowHeaderCaptionCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 6
@@ -131,11 +141,12 @@
     AnchorSideLeft.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Control = ShowHeaderCaptionCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 214
-    Width = 249
+    Left = 30
+    Height = 23
+    Top = 244
+    Width = 272
     Caption = 'HideHeaderCaptionForFloatingCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 7
@@ -147,15 +158,16 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 122
+    Left = 136
     Height = 27
-    Top = 286
-    Width = 284
+    Top = 313
+    Width = 342
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 6
-    BorderSpacing.Right = 10
-    ItemHeight = 0
+    BorderSpacing.Left = 7
+    BorderSpacing.Right = 12
+    ItemHeight = 19
     OnDrawItem = HeaderStyleComboBoxDrawItem
+    ParentFont = False
     Style = csDropDownList
     TabOrder = 10
   end
@@ -163,23 +175,25 @@
     AnchorSideLeft.Control = ShowHeaderCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrCenter
-    Left = 20
-    Height = 13
-    Top = 293
-    Width = 96
-    BorderSpacing.Left = 10
+    Left = 24
+    Height = 19
+    Top = 317
+    Width = 105
+    BorderSpacing.Left = 12
     Caption = 'HeaderStyleLabel'
     ParentColor = False
+    ParentFont = False
   end
   object FlattenHeadersCheckBox: TCheckBox
     AnchorSideLeft.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Control = HideHeaderCaptionForFloatingCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 238
-    Width = 164
+    Left = 30
+    Height = 23
+    Top = 267
+    Width = 175
     Caption = 'FlattenHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 8
@@ -188,11 +202,12 @@
     AnchorSideLeft.Control = FlattenHeadersCheckBox
     AnchorSideTop.Control = FlattenHeadersCheckBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 262
-    Width = 154
+    Left = 30
+    Height = 23
+    Top = 290
+    Width = 164
     Caption = 'FilledHeadersCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 9
@@ -201,11 +216,12 @@
     AnchorSideLeft.Control = FilledHeadersCheckBox
     AnchorSideTop.Control = HeaderStyleComboBox
     AnchorSideTop.Side = asrBottom
-    Left = 25
-    Height = 24
-    Top = 313
-    Width = 175
+    Left = 30
+    Height = 23
+    Top = 340
+    Width = 189
     Caption = 'HighlightFocusedCheckBox'
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 11
@@ -215,13 +231,14 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = SplitterWidthLabel
     AnchorSideTop.Side = asrCenter
-    Left = 119
-    Height = 23
-    Top = 74
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 131
+    Height = 27
+    Top = 93
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 10
     MinValue = 1
+    ParentFont = False
     TabOrder = 2
     Value = 1
     Visible = False
@@ -228,15 +245,16 @@
   end
   object HeaderAlignTopLabel: TLabel
     AnchorSideLeft.Control = DragThresholdLabel
-    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Control = DockSitesCanBeMinimized
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 347
-    Width = 117
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 398
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignTopLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignTopTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -244,10 +262,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 360
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 417
+    Width = 466
     Frequency = 10
     Max = 150
     OnChange = HeaderAlignTopTrackBarChange
@@ -254,7 +272,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 13
@@ -264,12 +283,13 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignTopLabel
     AnchorSideTop.Side = asrCenter
-    Left = 133
-    Height = 23
-    Top = 342
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 394
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 150
+    ParentFont = False
     TabOrder = 12
     Visible = False
   end
@@ -277,13 +297,14 @@
     AnchorSideLeft.Control = DragThresholdLabel
     AnchorSideTop.Control = HeaderAlignTopTrackBar
     AnchorSideTop.Side = asrBottom
-    Left = 10
-    Height = 13
-    Top = 417
-    Width = 120
-    BorderSpacing.Top = 10
+    Left = 12
+    Height = 19
+    Top = 484
+    Width = 130
+    BorderSpacing.Top = 12
     Caption = 'HeaderAlignLeftLabel'
     ParentColor = False
+    ParentFont = False
   end
   object HeaderAlignLeftTrackBar: TTrackBar
     AnchorSideLeft.Control = Owner
@@ -291,10 +312,10 @@
     AnchorSideTop.Side = asrBottom
     AnchorSideRight.Control = DragThresholdTrackBar
     AnchorSideRight.Side = asrBottom
-    Left = 10
-    Height = 47
-    Top = 430
-    Width = 396
+    Left = 12
+    Height = 55
+    Top = 503
+    Width = 466
     Frequency = 10
     Max = 200
     OnChange = HeaderAlignLeftTrackBarChange
@@ -301,7 +322,8 @@
     PageSize = 10
     Position = 0
     Anchors = [akTop, akLeft, akRight]
-    BorderSpacing.Left = 10
+    BorderSpacing.Left = 12
+    ParentFont = False
     ParentShowHint = False
     ShowHint = True
     TabOrder = 15
@@ -311,13 +333,28 @@
     AnchorSideLeft.Side = asrBottom
     AnchorSideTop.Control = HeaderAlignLeftLabel
     AnchorSideTop.Side = asrCenter
-    Left = 136
-    Height = 23
-    Top = 412
-    Width = 50
-    BorderSpacing.Left = 6
+    Left = 149
+    Height = 27
+    Top = 480
+    Width = 59
+    BorderSpacing.Left = 7
     MaxValue = 200
+    ParentFont = False
     TabOrder = 14
     Visible = False
   end
+  object DockSitesCanBeMinimized: TCheckBox
+    AnchorSideLeft.Control = FilledHeadersCheckBox
+    AnchorSideTop.Control = HighlightFocusedCheckBox
+    AnchorSideTop.Side = asrBottom
+    Left = 30
+    Height = 23
+    Top = 363
+    Width = 185
+    Caption = 'DockSitesCanBeMinimized'
+    ParentFont = False
+    ParentShowHint = False
+    ShowHint = True
+    TabOrder = 16
+  end
 end
Index: components/anchordocking/anchordockoptionsdlg.pas
===================================================================
--- components/anchordocking/anchordockoptionsdlg.pas	(revision 59428)
+++ components/anchordocking/anchordockoptionsdlg.pas	(working copy)
@@ -37,6 +37,7 @@
     HeaderStyleLabel: TLabel;
     HideHeaderCaptionForFloatingCheckBox: TCheckBox;
     HighlightFocusedCheckBox: TCheckBox;
+    DockSitesCanBeMinimized: TCheckBox;
     ScaleOnResizeCheckBox: TCheckBox;
     ShowHeaderCaptionCheckBox: TCheckBox;
     ShowHeaderCheckBox: TCheckBox;
@@ -202,7 +203,7 @@
 
       HeaderAlignTopSpinEdit.Visible:=true;
       HeaderAlignTopTrackBar.Visible:=false;
-      HeaderAlignTopSpinEdit.AnchorToNeighbour(akTop,6,HighlightFocusedCheckBox);
+      HeaderAlignTopSpinEdit.AnchorToNeighbour(akTop,6,DockSitesCanBeMinimized);
       HeaderAlignTopLabel.AnchorVerticalCenterTo(HeaderAlignTopSpinEdit);
       UpdateHeaderAlignTopLabel;
 
@@ -299,6 +300,7 @@
   HeaderStyleLabel.Enabled:=HasHeaders;
   HeaderStyleComboBox.Enabled:=HasHeaders;
   HighlightFocusedCheckBox.Enabled:=HasHeaders;
+  DockSitesCanBeMinimized.Enabled:=HasHeaders;
 end;
 
 constructor TAnchorDockOptionsFrame.Create(TheOwner: TComponent);
@@ -356,6 +358,7 @@
   TheSettings.HeaderFilled:=FilledHeadersCheckBox.Checked;
   TheSettings.HeaderStyle:=TADHeaderStyle(HeaderStyleComboBox.ItemIndex);
   TheSettings.HeaderHighlightFocused:=HighlightFocusedCheckBox.Checked;
+  TheSettings.DockSitesCanBeMinimized:=DockSitesCanBeMinimized.Checked;
 end;
 
 procedure TAnchorDockOptionsFrame.LoadFromSettings(
@@ -429,6 +432,10 @@
   HighlightFocusedCheckBox.Checked:=TheSettings.HeaderHighlightFocused;
   HighlightFocusedCheckBox.Caption:=adrsHighlightFocused;
   HighlightFocusedCheckBox.Hint:=adrsHighlightFocusedHint;
+
+  DockSitesCanBeMinimized.Checked:=TheSettings.DockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Caption:=adrsDockSitesCanBeMinimized;
+  DockSitesCanBeMinimized.Hint:=adrsDockSitesCanBeMinimizedHint;
 end;
 
 end.
Index: components/anchordocking/anchordockpanel.pas
===================================================================
--- components/anchordocking/anchordockpanel.pas	(revision 59428)
+++ components/anchordocking/anchordockpanel.pas	(working copy)
@@ -55,7 +55,7 @@
   begin
 
     LayoutNode.NodeType:=adltnControl;
-    LayoutNode.Assign(Self);
+    LayoutNode.Assign(Self,false,false);
     LayoutNode.Name:={OneControl.}Name;
 
     TAnchorDockHostSite(OneControl).SaveLayout(LayoutTree,LayoutNode);
Index: components/anchordocking/anchordockstorage.pas
===================================================================
--- components/anchordocking/anchordockstorage.pas	(revision 59428)
+++ components/anchordocking/anchordockstorage.pas	(working copy)
@@ -64,6 +64,7 @@
     FTabPosition: TTabPosition;
     FWindowState: TWindowState;
     FControlLocation: TADLControlLocation;
+    FMinimized: Boolean;
     function GetAnchors(Site: TAnchorKind): string;
     function GetBottom: integer;
     function GetHeight: integer;
@@ -90,6 +91,7 @@
     procedure SetTop(const AValue: integer);
     procedure SetWidth(const AValue: integer);
     procedure SetWindowState(const AValue: TWindowState);
+    procedure SetMinimized(const AValue: boolean);
   public
     constructor Create;
     destructor Destroy; override;
@@ -96,7 +98,7 @@
     procedure Clear;
     function IsEqual(Node: TAnchorDockLayoutTreeNode): boolean;
     procedure Assign(Node: TAnchorDockLayoutTreeNode); overload;
-    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean=false); overload;
+    procedure Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean); overload;
     procedure LoadFromConfig(Config: TConfigStorage); overload;
     procedure LoadFromConfig(Path: string; Config: TRttiXMLConfig); overload;
     procedure SaveToConfig(Config: TConfigStorage); overload;
@@ -106,7 +108,7 @@
     procedure CheckConsistency; virtual;
 
     // simplifying
-    procedure Simplify(ExistingNames: TStrings);
+    procedure Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
     procedure DeleteNode(ChildNode: TAnchorDockLayoutTreeNode);
     function FindNodeBoundSplitter(ChildNode: TAnchorDockLayoutTreeNode;
                                    Side: TAnchorKind): TAnchorDockLayoutTreeNode;
@@ -135,6 +137,7 @@
     property Monitor: integer read FMonitor write SetMonitor;
     property HeaderPosition: TADLHeaderPosition read FHeaderPosition write SetHeaderPosition;
     property TabPosition: TTabPosition read FTabPosition write SetTabPosition;
+    property Minimized: Boolean read FMinimized write SetMinimized;
     function Count: integer;
     function IsSplitter: boolean;
     function IsRootWindow: boolean;
@@ -988,6 +991,13 @@
   IncreaseChangeStamp;
 end;
 
+procedure TAnchorDockLayoutTreeNode.SetMinimized(const AValue: boolean);
+begin
+  if FMinimized=AValue then exit;
+  FMinimized:=AValue;
+  IncreaseChangeStamp;
+end;
+
 procedure TAnchorDockLayoutTreeNode.SetTop(const AValue: integer);
 begin
   if Top=AValue then exit;
@@ -1084,6 +1094,7 @@
   BoundSplitterPos:=Node.BoundSplitterPos;
   WorkAreaRect:=Node.WorkAreaRect;
   Monitor:=Node.Monitor;
+  Minimized:=Node.Minimized;
   for a:=low(TAnchorKind) to high(TAnchorKind) do
     Anchors[a]:=Node.Anchors[a];
   while Count>Node.Count do Nodes[Count-1].Free;
@@ -1098,9 +1109,10 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean=false);
+procedure TAnchorDockLayoutTreeNode.Assign(AControl: TControl; OverrideBoundsRect: Boolean; AMinimized: Boolean);
 var
   AnchorControl: TControl;
+  ParentForm:TCustomForm;
   a: TAnchorKind;
 begin
   Name:=AControl.Name;
@@ -1109,12 +1121,18 @@
   else
     BoundsRect:=AControl.BoundsRect;
   Align:=AControl.Align;
+  Minimized:=AMinimized;
   if (AControl.Parent=nil) and (AControl is TCustomForm) then begin
     WindowState:=TCustomForm(AControl).WindowState;
     Monitor:=TCustomForm(AControl).Monitor.MonitorNum;
     WorkAreaRect:=TCustomForm(AControl).Monitor.WorkareaRect;
-  end else
-    WindowState:=GetParentForm(AControl).WindowState;
+  end else begin
+    ParentForm:=GetParentForm(AControl);
+    if assigned(ParentForm) then
+      WindowState:=ParentForm.WindowState
+    else
+      WindowState:=wsNormal;
+  end;
   if AControl is TCustomTabControl then
     TabPosition:=TCustomTabControl(AControl).TabPosition
   else
@@ -1137,6 +1155,7 @@
   Clear;
   Name:=Config.GetValue('Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue('Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue('Minimized',false);
   Left:=Config.GetValue('Bounds/Left',0);
   Top:=Config.GetValue('Bounds/Top',0);
   Width:=Config.GetValue('Bounds/Width',0);
@@ -1171,6 +1190,7 @@
   Clear;
   Name:=Config.GetValue(Path+'Name','');
   NodeType:=NameToADLTreeNodeType(Config.GetValue(Path+'Type',ADLTreeNodeTypeNames[adltnNone]));
+  Minimized:=Config.GetValue(Path+'Minimized',false);
   Left:=Config.GetValue(Path+'Bounds/Left',0);
   Top:=Config.GetValue(Path+'Bounds/Top',0);
   Width:=Config.GetValue(Path+'Bounds/Width',0);
@@ -1219,6 +1239,7 @@
                                           ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue('Header/TabPosition',ADLTabPostionNames[TabPosition],
                                              ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue('Minimized',Minimized,False);
   Config.SetDeleteValue('Monitor',Monitor,0);
   Config.SetDeleteValue('ChildCount',Count,0);
   for i:=1 to Count do begin
@@ -1252,6 +1273,7 @@
                                                ADLHeaderPositionNames[adlhpAuto]);
   Config.SetDeleteValue(Path+'Header/TabPosition',ADLTabPostionNames[TabPosition],
                                                   ADLTabPostionNames[tpTop]);
+  Config.SetDeleteValue(Path+'Minimized',Minimized,False);
   Config.SetDeleteValue(Path+'Monitor',Monitor,0);
   Config.SetDeleteValue(Path+'ChildCount',Count,0);
   for i:=1 to Count do
@@ -1397,7 +1419,7 @@
   end;
 end;
 
-procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings);
+procedure TAnchorDockLayoutTreeNode.Simplify(ExistingNames: TStrings; ParentMinimized:boolean);
 { Simplification rules:
    1. Control nodes without existing name are deleted.
    2. Empty layouts and pages are deleted
@@ -1406,16 +1428,18 @@
 var
   i: Integer;
   ChildNode: TAnchorDockLayoutTreeNode;
+  NodeMinimized:boolean;
 begin
   // simplify children
   i:=Count-1;
   while i>=0 do begin
     ChildNode:=Nodes[i];
-    ChildNode.Simplify(ExistingNames);
+    NodeMinimized:=ParentMinimized or ChildNode.Minimized;
+    ChildNode.Simplify(ExistingNames,NodeMinimized);
 
     if (ChildNode.NodeType=adltnControl) then begin
       // leaf node => check if there is a control
-      if (ChildNode.Name='') or (ExistingNames.IndexOf(ChildNode.Name)<0) then
+      if (ChildNode.Name='') or ((ExistingNames.IndexOf(ChildNode.Name)<0) and (not NodeMinimized)) then
         DeleteNode(ChildNode);
     end else if ChildNode.IsSplitter then begin
       // splitter
@@ -1424,7 +1448,7 @@
         ChildNode[0].Free;
     end else if ChildNode.NodeType=adltnCustomSite then begin
       // custom dock site
-    end else if ChildNode.Count=0 then begin
+    end else if (ChildNode.Count=0)and(not NodeMinimized) then begin
       // inner node without child => delete
       DeleteNode(ChildNode);
     end else if (ChildNode.Count=1)
Index: components/anchordocking/anchordockstr.pas
===================================================================
--- components/anchordocking/anchordockstr.pas	(revision 59428)
+++ components/anchordocking/anchordockstr.pas	(working copy)
@@ -8,6 +8,7 @@
 
 resourcestring
   adrsClose = 'Close';
+  adrsMinimize = 'Minimize';
   adrsQuit = 'Quit %s';
   adrsTabPosition = 'Tab position';
   adrsMovePageRight = 'Move page right';
@@ -82,6 +83,8 @@
   adrsFilledHeadersHint = 'Fill headers of docked controls';
   adrsHighlightFocused = 'Highlight focused';
   adrsHighlightFocusedHint = 'Highlight header of focused docked control';
+  adrsDockSitesCanBeMinimized = 'Dock sites can be minimized';
+  adrsDockSitesCanBeMinimizedHint = 'Dock sites can be minimized';
 
 implementation
 
Index: components/anchordocking/design/anchordesktopoptions.pas
===================================================================
--- components/anchordocking/design/anchordesktopoptions.pas	(revision 59428)
+++ components/anchordocking/design/anchordesktopoptions.pas	(working copy)
@@ -272,7 +272,7 @@
         // custom dock site
         LayoutNode:=FTree.NewNode(FTree.Root);
         LayoutNode.NodeType:=adltnCustomSite;
-        LayoutNode.Assign(AForm);
+        LayoutNode.Assign(AForm,false,false);
         // can have one normal dock site
         Site:=TAnchorDockManager(AForm.DockManager).GetChildSite;
         if Site<>nil then begin
@@ -287,7 +287,7 @@
         raise EAnchorDockLayoutError.Create('invalid root control for save: '+DbgSName(AControl));
     end;
     // remove invisible controls
-    FTree.Root.Simplify(VisibleControls);
+    FTree.Root.Simplify(VisibleControls,false);
   finally
     VisibleControls.Free;
     SavedSites.Free;

<?xml version="1.0" encoding="utf-8"?>
<CONFIG>
  <MainConfig>
    <Nodes ChildCount="1">
      <Item1 Name="AnchorDockPanel1" Type="CustomSite" ChildCount="1">
        <Bounds Top="43" Left="45" Width="568" Height="418"/>
        <Anchors Align="Client"/>
        <Item1 Name="AnchorDockSite3" Type="Layout" ChildCount="3">
          <Bounds Top="1" Left="1" Width="524" Height="325"/>
          <Anchors Align="Client"/>
          <Item1 Name="SourceEditor1" Type="Control">
            <Bounds Width="524" Height="171"/>
            <Anchors Bottom="AnchorDockSplitter1"/>
          </Item1>
          <Item2 Name="AnchorDockSplitter1" Type="SplitterHorizontal">
            <Bounds Top="171" Width="524" Height="4"/>
          </Item2>
          <Item3 Name="DebugOutput" Type="Control">
            <Bounds Top="175" Width="524" Height="150"/>
            <Anchors Top="AnchorDockSplitter1"/>
          </Item3>
        </Item1>
      </Item1>
    </Nodes>
  </MainConfig>
  <Settings DockSitesCanBeMinimized="True"/>
</CONFIG>