Fatal error: Uncaught Error: Interface "MediaWiki\Notification\NotificationHandler" not found in /home/floten1/q.tenbergen.ca/extensions/Echo/includes/EchoNotificationHandler.php:12 Stack trace: #0 {main} thrown in /home/floten1/q.tenbergen.ca/extensions/Echo/includes/EchoNotificationHandler.php on line 12