Fatal error: Uncaught Error: Interface "ILIAS\COPage\PageLinker" not found in /var/www/html/ilias/components/ILIAS/LearningModule/Presentation/class.ilLMPresentationLinker.php:23 Stack trace: #0 {main} thrown in /var/www/html/ilias/components/ILIAS/LearningModule/Presentation/class.ilLMPresentationLinker.php on line 23