Fatal error: Uncaught Error: Interface "ilCertificatePlaceholderDescription" not found in /var/www/html/ilias/components/ILIAS/Certificate/classes/Placeholder/Description/class.ilObjectCustomUserFieldsPlaceholderDescription.php:21 Stack trace: #0 {main} thrown in /var/www/html/ilias/components/ILIAS/Certificate/classes/Placeholder/Description/class.ilObjectCustomUserFieldsPlaceholderDescription.php on line 21