Fatal error: Uncaught Error: Class "ILIAS\UI\Implementation\Component\Tree\Node\Node" not found in /var/www/html/ilias/components/ILIAS/UI/src/Implementation/Component/Tree/Node/Simple.php:30 Stack trace: #0 {main} thrown in /var/www/html/ilias/components/ILIAS/UI/src/Implementation/Component/Tree/Node/Simple.php on line 30