Fatal error: Uncaught Error: Class "yii\validators\Validator" not found in /users/quirl/www/filemanager/spark/protected/humhub/modules/space/components/UrlValidator.php:23 Stack trace: #0 {main} thrown in /users/quirl/www/filemanager/spark/protected/humhub/modules/space/components/UrlValidator.php on line 23