Fatal error: Uncaught Error: Class "OCP\EventDispatcher\Event" not found in /home/tzuovhm/tzuovhm/lib_/public/DB/Events/AddMissingColumnsEvent.php:19 Stack trace: #0 {main} thrown in /home/tzuovhm/tzuovhm/lib_/public/DB/Events/AddMissingColumnsEvent.php on line 19