Fatal error: Uncaught Error: Class 'Symfony\Contracts\EventDispatcher\Event' not found in /home/mattiapa/cloud2.mprnl.fr/owncloud/lib/public/Notification/Events/RegisterNotifierEvent.php:47 Stack trace: #0 {main} thrown in /home/mattiapa/cloud2.mprnl.fr/owncloud/lib/public/Notification/Events/RegisterNotifierEvent.php on line 47