anchor.diff:  
           //update Markdown code-blocks
           if AndApplyTheme then
  -          UpdateColoredRangesInLexer(F, false);
  +          DoApplyThemeToEditor(F, false);
         end;
       end;
   
  
positive.code:   end;
  end;
  
  procedure UpdateColoredRangesInLexer(Frame: TEditorFrame; APrimaryEditor: boolean);
  var
    Ada: TATAdapterEControl;
    Ed: TATSynEdit;
  begin
    //current code is bad:
    //Ada.UpdateRangesFoldAndColored causes issue #4233
    exit;
  
    if APrimaryEditor then
      Ed:= Frame.Ed1
    else
      Ed:= Frame.Ed2;
    Ada:= TATAdapterEControl(Frame.Adapter[Ed]);
    if Assigned(Ada) and Assigned(Ada.AnClient) then
    begin
      Ada.AnClient.CriSecForData.Enter;
      try
        Ada.UpdateRangesFoldAndColored;
      finally
        Ada.AnClient.CriSecForData.Leave;
      end;
    end;
  end;
  
  
negative.code: 
        //update Markdown code-blocks
        if AndApplyTheme then
          DoApplyThemeToEditor(F, true);
      end;
  
      if not F.EditorsLinked then
  