Fatal error: Uncaught Error: Interface "ilCtrlBaseClassInterface" not found in /var/www/html/ilias/components/ILIAS/Accessibility/classes/class.ilAccessibilityControlConceptGUI.php:23 Stack trace: #0 {main} thrown in /var/www/html/ilias/components/ILIAS/Accessibility/classes/class.ilAccessibilityControlConceptGUI.php on line 23