Fatal error: Uncaught Error: Interface "ILIAS\Setup\Agent" not found in /var/www/html/ilias/components/ILIAS/UICore/classes/Setup/class.ilUICoreSetupAgent.php:21 Stack trace: #0 {main} thrown in /var/www/html/ilias/components/ILIAS/UICore/classes/Setup/class.ilUICoreSetupAgent.php on line 21