Fatal error: Uncaught Error: Using $this when not in object context in /users/quirl/www/filemanager/spark/protected/humhub/modules/space/notifications/views/mails/membershipRolesChanged.php:20 Stack trace: #0 {main} thrown in /users/quirl/www/filemanager/spark/protected/humhub/modules/space/notifications/views/mails/membershipRolesChanged.php on line 20