anchor.diff:    N: integer;
     S: string;
   begin
  +  if FBusyClickUi then exit;
  +  FBusyClickUi:= true;
  +
     N:=ListboxUi.ItemIndex;
     if N>0 then
       S:= ListboxUi.Items[N]
  
positive.code:     procedure ListboxSyntaxClick(Sender: TObject);
      procedure ListboxUIClick(Sender: TObject);
    private
      procedure Localize;
      function GetEnableLexerThemes: boolean;
      function GetEnableSync: boolean;
  
negative.code:     S:= '';
    ThemeUiSetter(S);
  
    if chkSync.Checked and chkEnableLex.Checked then
    begin
      if S='' then
        N:= 0
  