anchor.diff:    TfpgListBoxStrings = class(TStringList)
     protected
       ListBox: TfpgTextListBox;
  -    procedure   SetUpdateState(Updating: Boolean); override;
     public
       constructor Create(AListBox: TfpgTextListBox);
       destructor  Destroy; override;
  
positive.code: 
  { TfpgListBoxStrings }
  
  procedure TfpgListBoxStrings.SetUpdateState(Updating: Boolean);
  begin
    inherited SetUpdateState(Updating);
    // do nothing extra for now
  end;
  
  constructor TfpgListBoxStrings.Create(AListBox: TfpgTextListBox);
  begin
    inherited Create;
  
negative.code:   r: TfpgRect;
  begin
    //if FUpdateCount > 0 then
    //  Exit; //==>
  
    inherited HandlePaint;
    Canvas.ClearClipRect;
  