Fatal error: Uncaught Error: Class "ilContainerGUI" not found in /var/www/html/ilias/components/ILIAS/Category/classes/class.ilObjCategoryGUI.php:36 Stack trace: #0 {main} thrown in /var/www/html/ilias/components/ILIAS/Category/classes/class.ilObjCategoryGUI.php on line 36