Fatal error: Uncaught Error: Class "Yii" not found in /users/quirl/www/filemanager/spark/protected/humhub/modules/user/activities/views/mail/plaintext/userFollow.php:9 Stack trace: #0 {main} thrown in /users/quirl/www/filemanager/spark/protected/humhub/modules/user/activities/views/mail/plaintext/userFollow.php on line 9