Fatal error: Uncaught Error: Class "yii\base\Event" not found in /users/quirl/www/filemanager/spark/protected/humhub/events/OembedFetchEvent.php:8 Stack trace: #0 {main} thrown in /users/quirl/www/filemanager/spark/protected/humhub/events/OembedFetchEvent.php on line 8