Fatal error: Uncaught Error: Interface "ILIAS\COPage\Page\PageManagerInterface" not found in /var/www/html/ilias/components/ILIAS/COPage/Page/class.PageManager.php:26 Stack trace: #0 {main} thrown in /var/www/html/ilias/components/ILIAS/COPage/Page/class.PageManager.php on line 26