PHP:
Fatal error: Uncaught Error: Class "WP_Widget" not found in /www/habi.gna.ch/doc/wp-includes/widgets/class-wp-widget-custom-html.php:17 Stack trace: #0 {main} thrown in /www/habi.gna.ch/doc/wp-includes/widgets/class-wp-widget-custom-html.php on line 17