Fatal error: Uncaught Error: Class "Drupal\Core\Entity\ContentEntityDeleteForm" not found in /home/www/drupal8/test/modules/webform/src/Form/WebformSubmissionDeleteForm.php:14 Stack trace: #0 {main} thrown in /home/www/drupal8/test/modules/webform/src/Form/WebformSubmissionDeleteForm.php on line 14