Fatal error: Uncaught Error: Class "WP_Widget" not found in /home/pacs/vcg00/users/compgen.de/wordpress/wp-includes/widgets/class-wp-nav-menu-widget.php:17 Stack trace: #0 {main} thrown in /home/pacs/vcg00/users/compgen.de/wordpress/wp-includes/widgets/class-wp-nav-menu-widget.php on line 17