Fatal error: Uncaught Error: Class "App\Engine\LegacyHandler\LegacyHandler" not found in /var/www/html/core/backend/UserPreferences/LegacyHandler/FullNameHandler.php:9 Stack trace: #0 {main} thrown in /var/www/html/core/backend/UserPreferences/LegacyHandler/FullNameHandler.php on line 9