diff --git a/ide/main.pp b/ide/main.pp
index 45ddacc3ea..5f8eec0c0b 100644
--- a/ide/main.pp
+++ b/ide/main.pp
@@ -12600,11 +12600,16 @@ begin
           SearchResultsView.ShowOnTop;
           SourceEditorManager.ShowActiveWindowOnTop(True);
         end;
-        SrcEdit.EditorComponent.LogicalCaretXY:=LogCaretXY;
-        if not SrcEdit.IsLocked then
-          SrcEdit.CenterCursor(True);
-        with SrcEdit.EditorComponent do begin
-          LeftChar:= Math.Max(LogCaretXY.X-CharsInWindow,1);
+        try
+          SrcEdit.BeginUpdate;
+          SrcEdit.EditorComponent.LogicalCaretXY:=LogCaretXY;
+          if not SrcEdit.IsLocked then
+            SrcEdit.CenterCursor(True);
+          with SrcEdit.EditorComponent do begin
+            LeftChar:= Math.Max(LogCaretXY.X-CharsInWindow,1);
+          end;
+        finally
+          SrcEdit.EndUpdate;
         end;
         SrcEdit.ErrorLine:=LogCaretXY.Y;
       end;
@@ -13895,17 +13900,20 @@ begin
   if NewX<1 then NewX:=1;
   if NewY<1 then NewY:=1;
   //debugln(['[TMainIDE.DoJumpToCodePos] ',NewX,',',NewY,',',NewTopLine]);
-  with NewSrcEdit.EditorComponent do 
-  begin
-    MoveLogicalCaretIgnoreEOL(Point(NewX,NewY));
+  try
+    NewSrcEdit.BeginUpdate;
+    NewSrcEdit.EditorComponent.MoveLogicalCaretIgnoreEOL(Point(NewX,NewY));
     if not NewSrcEdit.IsLocked then begin
       if NewTopLine < 1 then
         NewSrcEdit.CenterCursor(True)
       else
-        TopLine:=NewTopLine;
+        NewSrcEdit.TopLine:=NewTopLine;
     end;
     //DebugLn('TMainIDE.DoJumpToCodePos NewY=',dbgs(NewY),' ',dbgs(TopLine),' ',dbgs(NewTopLine));
-    LeftChar:=Max(NewX-CharsInWindow,1);
+    with NewSrcEdit.EditorComponent do
+      LeftChar:=Max(NewX - CharsInWindow, 1);
+  finally
+    NewSrcEdit.EndUpdate;
   end;
   if MarkLine then
     NewSrcEdit.ErrorLine := NewY;
@@ -14994,9 +15002,14 @@ begin
 
   SourceEditorManager.ActiveEditor := AnEditor;
   SourceEditorManager.ShowActiveWindowOnTop(True);
-  AnEditor.EditorComponent.GotoBookMark(ID);
-  if not AnEditor.IsLocked then
-    AnEditor.CenterCursor(True);
+  try
+    AnEditor.BeginUpdate;
+    AnEditor.EditorComponent.GotoBookMark(ID);
+    if not AnEditor.IsLocked then
+      AnEditor.CenterCursor(True);
+  finally
+    AnEditor.EndUpdate;
+  end;
 end;
 
 //this is fired when the editor is focused, changed, ?.  Anything that causes the status change
diff --git a/ide/sourceeditor.pp b/ide/sourceeditor.pp
index e6dbce00c3..80f3b21c08 100644
--- a/ide/sourceeditor.pp
+++ b/ide/sourceeditor.pp
@@ -1198,6 +1198,16 @@ implementation
 
 {$R *.lfm}
 
+const
+  (* SoftCenter are th visible Lines in the Editor where the caret can be locateted,
+     without CenterCursor adjusting the topline.
+     SoftCenter is defined by the amount of lines on the top/bottom of fthe editor,
+     which are *not* part of it.
+  *)
+  SoftCenterFactor  = 5;  // One fifth of the "LinesInWindow"on each side (top/bottom)
+  SoftCenterMinimum = 1;
+  SoftCenterMaximum = 8;
+
 var
   SourceCompletionTimer: TIdleTimer = nil;
   SourceCompletionCaretXY: TPoint;
@@ -4250,16 +4260,21 @@ end;
 -------------------------------------------------------------------------------}
 procedure TSourceEditor.CenterCursor(SoftCenter: Boolean = False);
 var
-  NewTopLine: integer;
-  Y, CurTopLine, LinesInWin, MinLines: Integer;
+  Y, CurTopLine, LinesInWin, MinLines, NewTopLine: Integer;
 begin
+  LinesInWin := EditorComponent.LinesInWindow;
+  CurTopLine := EditorComponent.TopView;
+  Y := EditorComponent.TextIndexToViewPos(EditorComponent.CaretY);
+
   if SoftCenter then begin
-    CurTopLine := EditorComponent.TopLine;
-    LinesInWin := EditorComponent.LinesInWindow;
-    MinLines := Min(Max(LinesInWin div 5, 1), 5);
-    Y := EditorComponent.CaretY;
-    if (Y <= CurTopLine) or (Y >= CurTopLine + LinesInWin)
-    then
+    MinLines := Min(
+      Min( Max(LinesInWin div SoftCenterFactor, SoftCenterMinimum),
+           SoftCenterMaximum),
+      Max(LinesInWin div 2 - 1, 0) // make sure there is at least one line in the soft center
+      );
+
+    if (Y <= CurTopLine) or (Y >= CurTopLine + LinesInWin) then
+      // Caret not yet visible => hard-center
       NewTopLine := Max(1, Y - (LinesInWin div 2))
     else
     if Y < CurTopLine + MinLines then
@@ -4271,9 +4286,11 @@ begin
       NewTopLine := CurTopLine;
   end
   else
-    NewTopLine:=EditorComponent.CaretY-((EditorComponent.LinesInWindow-1) div 2);
-  if NewTopLine<1 then NewTopLine:=1;
-  EditorComponent.TopLine:=NewTopLine;
+    // not using SoftCenter
+    NewTopLine := Max(1, Y - (LinesInWin div 2));
+
+  if NewTopLine < 1 then NewTopLine := 1;
+  EditorComponent.TopView := NewTopLine;
 end;
 
 function TSourceEditor.TextToScreenPosition(const Position: TPoint): TPoint;
@@ -4404,16 +4421,23 @@ end;
 
 function TSourceEditor.IsCaretOnScreen(ACaret: TPoint; UseSoftCenter: Boolean = False): Boolean;
 var
-  LinesInWin, MinLines: Integer;
+  LinesInWin, MinLines, CurTopLine, Y: Integer;
 begin
+  LinesInWin := EditorComponent.LinesInWindow;
+  CurTopLine := EditorComponent.TopView;
+  Y := EditorComponent.TextIndexToViewPos(EditorComponent.CaretY);
   if UsesoftCenter then begin
-    LinesInWin := EditorComponent.LinesInWindow;
-    MinLines := Min(Max(LinesInWin div 5, 1), 5);
+    MinLines := Min(
+      Min( Max(LinesInWin div SoftCenterFactor, SoftCenterMinimum),
+           SoftCenterMaximum),
+      Max(LinesInWin div 2 - 1, 0) // make sure there is at least one line in the soft center
+      );
   end
   else
     MinLines := 0;
-  Result := (ACaret.y >= FEditor.TopLine + MinLines) and
-            (ACaret.Y <= FEditor.TopLine + FEditor.LinesInWindow - MinLines) and
+
+  Result := (Y >= CurTopLine + MinLines) and
+            (Y <= CurTopLine + LinesInWin - MinLines) and
             (ACaret.X >= FEditor.LeftChar) and
             (ACaret.X <= FEditor.LeftChar + FEditor.CharsInWindow);
 end;
diff --git a/ide/sourcesyneditor.pas b/ide/sourcesyneditor.pas
index a43e5c6bc4..efe0d5c8a6 100644
--- a/ide/sourcesyneditor.pas
+++ b/ide/sourcesyneditor.pas
@@ -54,7 +54,9 @@ type
     function CreateGutter(AOwner : TSynEditBase; AFoldedLinesView: TSynEditFoldedView;
                           ATextDrawer: TheTextDrawer): TSynGutter; override;
   public
+    function TextIndexToViewPos(aTextIndex : Integer) : Integer;
     property IDEGutterMarks: TIDESynGutterMarks read GetIDEGutterMarks;
+    property TopView;
     property TextBuffer;
   end;
 
@@ -118,6 +120,11 @@ begin
   Result := TIDESynGutter.Create(AOwner, AFoldedLinesView, ATextDrawer);
 end;
 
+function TIDESynEditor.TextIndexToViewPos(aTextIndex: Integer): Integer;
+begin
+  Result := TextView.TextIndexToViewPos(aTextIndex - 1);
+end;
+
 { TIDESynGutter }
 
 procedure TIDESynGutter.CreateDefaultGutterParts;