diff --git a/ide/sourceeditor.pp b/ide/sourceeditor.pp
index a1e8205080..1a19695ab4 100644
--- a/ide/sourceeditor.pp
+++ b/ide/sourceeditor.pp
@@ -149,6 +149,7 @@ type
 
   TSourceEditorSharedValues = class
   private
+    FExecutionMark: TSourceMark;
     FSharedEditorList: TFPList; // list of TSourceEditor sharing one TSynEdit
     FExecutionLine: integer;
     FModified: boolean;
@@ -166,7 +167,9 @@ type
     property  OtherSharedEditors[Caller: TSourceEditor; Index: Integer]: TSourceEditor
               read GetOtherSharedEditors;
     property Modified: Boolean read FModified write SetModified;
+    procedure CreateExecutionMark;
     property ExecutionLine: Integer read FExecutionLine write FExecutionLine;
+    property ExecutionMark: TSourceMark read FExecutionMark write FExecutionMark;
   public
     constructor Create;
     destructor Destroy; override;
@@ -197,7 +200,6 @@ type
     FSyntaxHighlighterType: TLazSyntaxHighlighter;
     FErrorLine: integer;
     FErrorColumn: integer;
-    FExecutionMark: TSourceMark;
     FLineInfoNotification: TIDELineInfoNotification;
 
     FOnEditorChange: TNotifyEvent;
@@ -1977,16 +1979,27 @@ begin
   Result := FSharedEditorList.Count - 1;
 end;
 
+procedure TSourceEditorSharedValues.CreateExecutionMark;
+begin
+  FExecutionMark := TSourceMark.Create(SharedEditors[0], nil);
+  SourceEditorMarks.Add(FExecutionMark);
+  FExecutionMark.LineColorAttrib := ahaExecutionPoint;
+  FExecutionMark.Priority := 1;
+end;
+
 constructor TSourceEditorSharedValues.Create;
 begin
   FSharedEditorList := TFPList.Create;
   BookmarkEventLock := 0;
   FExecutionLine:=-1;
+  FExecutionMark := nil;
 end;
 
 destructor TSourceEditorSharedValues.Destroy;
 begin
   FreeAndNil(FSharedEditorList);
+  // no need to care about ExecutionMark, it was removed in EditorClose
+  // via: SourceEditorMarks.DeleteAllForEditor(Self);
   inherited Destroy;
 end;
 
@@ -2015,7 +2028,6 @@ Begin
   FSyntaxHighlighterType:=lshNone;
   FErrorLine:=-1;
   FErrorColumn:=-1;
-  FExecutionMark := nil;
   FHasExecutionMarks := False;
   FMarksRequested := False;
   FSyncroLockCount := 0;
@@ -3337,39 +3349,38 @@ end;
 procedure TSourceEditor.UpdateExecutionSourceMark;
 var
   BreakPoint: TIDEBreakPoint;
+  ExecutionMark: TSourceMark;
 begin
-  if (FExecutionMark = nil) then
-  begin
-    FExecutionMark := TSourceMark.Create(Self, nil);
-    SourceEditorMarks.Add(FExecutionMark);
-    FExecutionMark.LineColorAttrib := ahaExecutionPoint;
-    FExecutionMark.Priority := 1;
-  end;
+  ExecutionMark := FSharedValues.ExecutionMark;
+  if ExecutionMark = nil then exit;
 
-  if FExecutionMark.Visible then
-    FEditor.InvalidateLine(FExecutionMark.Line);
-  FExecutionMark.Visible := ExecutionLine <> -1;
-  if FExecutionMark.Visible then
+  if ExecutionMark.Visible then
   begin
-    FExecutionMark.Line := ExecutionLine;
-    FEditor.InvalidateLine(FExecutionMark.Line);
     if SourceEditorMarks.FindBreakPointMark(Self, ExecutionLine) <> nil then
     begin
       BreakPoint := DebugBoss.BreakPoints.Find(Self.FileName, ExecutionLine);
       if (BreakPoint <> nil) and (not BreakPoint.Enabled) then
-        FExecutionMark.ImageIndex := SourceEditorMarks.CurrentLineDisabledBreakPointImg
+        ExecutionMark.ImageIndex := SourceEditorMarks.CurrentLineDisabledBreakPointImg
       else
-        FExecutionMark.ImageIndex := SourceEditorMarks.CurrentLineBreakPointImg;
+        ExecutionMark.ImageIndex := SourceEditorMarks.CurrentLineBreakPointImg;
     end
     else
-      FExecutionMark.ImageIndex := SourceEditorMarks.CurrentLineImg;
+      ExecutionMark.ImageIndex := SourceEditorMarks.CurrentLineImg;
   end;
 end;
 
 procedure TSourceEditor.SetExecutionLine(NewLine: integer);
 begin
   if ExecutionLine=NewLine then exit;
-  FSharedValues.ExecutionLine:=NewLine;
+  if (FSharedValues.ExecutionMark = nil) then begin
+    if NewLine = -1 then
+      exit;
+    FSharedValues.CreateExecutionMark;
+  end;
+  FSharedValues.ExecutionLine := NewLine;
+  FSharedValues.ExecutionMark.Visible := NewLine <> -1;
+  if NewLine <> -1 then
+    FSharedValues.ExecutionMark.Line := NewLine;
   UpdateExecutionSourceMark;
 end;
 
@@ -8346,8 +8357,9 @@ begin
         AMark.AddSourceEditor(Editor.FSharedValues.SharedEditors[i]);
   end;
 
-  if AMark.IsBreakPoint and (Editor.FExecutionMark <> nil) and
-     (AMark.Line = Editor.ExecutionLine)
+  if ( AMark.IsBreakPoint and (Editor.FSharedValues.ExecutionMark <> nil) and
+       (AMark.Line = Editor.ExecutionLine)
+     ) or (AMark = Editor.FSharedValues.ExecutionMark)
   then
     Editor.UpdateExecutionSourceMark;
 end;
diff --git a/ide/sourcemarks.pas b/ide/sourcemarks.pas
index 77adfa8a59..8574e66c44 100644
--- a/ide/sourcemarks.pas
+++ b/ide/sourcemarks.pas
@@ -125,6 +125,7 @@ type
     FSourceMarks: TSourceMarks;
     FSourceEditorID: TObject;
     FSynMarks: TSourceSynMarkList;
+    FSynMarkLock: Integer;
     FData: TObject;
     FHandlers: array[TSourceMarkHandler] of TMethodList;
     FLine: integer;
@@ -146,7 +147,7 @@ type
     procedure AddHandler(HandlerType: TSourceMarkHandler;
                          const Handler: TMethod);
     procedure DoPositionChanged; virtual;
-    procedure DoLineUpdate; virtual;
+    procedure DoLineUpdate(Force: Boolean = False); virtual;
     function  EditorUpdateRequired: Boolean; virtual; // called to check if we need to update the editor if a property is changed
     procedure SetColumn(const Value: Integer); //override;
     procedure SetData(const AValue: TObject); virtual;
@@ -461,8 +462,7 @@ var
   i: Integer;
 begin
   for i := 0 to Count - 1 do
-    if Visible then
-      Items[i].GetEdit.InvalidateLine(ALine);
+    Items[i].GetEdit.InvalidateLine(ALine);
 end;
 
 procedure TSourceSynMarkList.DeleteWithSourceEditor(
@@ -542,7 +542,8 @@ procedure TSourceMark.SetPriority(const AValue: integer);
 begin
   if FPriority = AValue then exit;
   FPriority := AValue;
-  FSynMarks.Priority := AValue;
+  if FSynMarkLock = 0 then
+    FSynMarks.Priority := AValue;
 end;
 
 function TSourceMark.GetSourceEditorID: TObject;
@@ -570,11 +571,14 @@ end;
 
 procedure TSourceMark.SynMarkChanged(Sender: TObject);
 begin
+  // Only read Value from Mark => Do not write back to Mark(s)
+  inc(FSynMarkLock);
   Line := TSourceSynMark(Sender).Line;
   Column := TSourceSynMark(Sender).Column;
   Priority := TSourceSynMark(Sender).Priority;
   ImageIndex := TSourceSynMark(Sender).ImageIndex;
   Visible := TSourceSynMark(Sender).Visible;
+  dec(FSynMarkLock);
 end;
 
 procedure TSourceMark.SetLineColorBackGround(const AValue: TColor);
@@ -582,6 +586,7 @@ begin
   if FLineColorBackGround=AValue then exit;
   FLineColorBackGround:=AValue;
   DoLineUpdate;
+  Changed;
 end;
 
 procedure TSourceMark.SetLineColorForeGround(const AValue: TColor);
@@ -589,6 +594,7 @@ begin
   if FLineColorForeGround=AValue then exit;
   FLineColorForeGround:=AValue;
   DoLineUpdate;
+  Changed;
 end;
 
 procedure TSourceMark.SetLineColorAttrib(
@@ -597,6 +603,7 @@ begin
   if FLineColorAttrib=AValue then exit;
   FLineColorAttrib:=AValue;
   DoLineUpdate;
+  Changed;
 end;
 
 procedure TSourceMark.SetIsBreakPoint(const AValue: boolean);
@@ -604,14 +611,17 @@ begin
   if FIsBreakPoint=AValue then exit;
   FIsBreakPoint:=AValue;
   DoLineUpdate;
+  Changed;
 end;
 
 procedure TSourceMark.SetVisible(const AValue: boolean);
 begin
   if Visible = AValue then Exit;
   FVisible := AValue;
-  FSynMarks.Visible := AValue;
-  if EditorUpdateRequired then DoLineUpdate;
+  if FSynMarkLock = 0 then
+    FSynMarks.Visible := AValue;
+  if EditorUpdateRequired then DoLineUpdate(True);
+  Changed;
 end;
 
 procedure TSourceMark.DoPositionChanged;
@@ -623,11 +633,11 @@ begin
     TNotifyEvent(FHandlers[smhPositionChanged][i])(Self);
 end;
 
-procedure TSourceMark.DoLineUpdate;
+procedure TSourceMark.DoLineUpdate(Force: Boolean = False);
 begin
   if Line <= 0 then Exit;
-  FSynMarks.InvalidateLine(Line);
-  Changed;
+  if Visible or Force then
+    FSynMarks.InvalidateLine(Line);
 end;
 
 procedure TSourceMark.SetData(const AValue: TObject);
@@ -657,7 +667,8 @@ begin
   if Column=Value then exit;
   if FSourceMarks<>nil then FSourceMarks.fSortedItems.Remove(Self);
   FColumn := Value;
-  FSynMarks.Column := Value;
+  if FSynMarkLock = 0 then
+    FSynMarks.Column := Value;
   if FSourceMarks<>nil then FSourceMarks.fSortedItems.Add(Self);
   DoPositionChanged;
 end;
@@ -666,7 +677,8 @@ procedure TSourceMark.SetImage(const Value: Integer);
 begin
   if ImageIndex=Value then exit;
   FImage := Value;
-  FSynMarks.ImageIndex := Value;
+  if FSynMarkLock = 0 then
+    FSynMarks.ImageIndex := Value;
   Changed;
 end;
 
@@ -676,14 +688,17 @@ begin
   if EditorUpdateRequired then DoLineUpdate;
   if FSourceMarks<>nil then FSourceMarks.fSortedItems.Remove(Self);
   FLine := Value;
-  FSynMarks.Line := Value;
+  if FSynMarkLock = 0 then
+    FSynMarks.Line := Value;
   if FSourceMarks<>nil then FSourceMarks.fSortedItems.Add(Self);
   DoPositionChanged;
   if EditorUpdateRequired then DoLineUpdate;
+  Changed;
 end;
 
 constructor TSourceMark.Create(TheOwner: TSourceEditorInterface; TheData: TObject);
 begin
+  FSynMarkLock := 0;
   FSynMarks := TSourceSynMarkList.Create;
   FSynMarks.OnChange := @SynMarkChanged;
   FSynMarks.Add(TSourceSynMark.Create(Self, TheOwner));