Fatal error: Uncaught Error: Class "Drupal\package_manager\Event\SandboxValidationEvent" not found in /home/qcsvlel/www/core/modules/package_manager/src/Event/PreApplyEvent.php:14 Stack trace: #0 {main} thrown in /home/qcsvlel/www/core/modules/package_manager/src/Event/PreApplyEvent.php on line 14