Default Values Errormessage of project

if i go to the default values of my project, an Errormessage apears!

Undefined variable: str_js | Script: D:\Programme\NetMake\v9\wwwroot\scriptcase\devel\class\page\nmPagePreviewEditorHtml.class.php linha: 340 !

Screenshot 2022-05-02 154934|497x303