Fatal error: Uncaught Error: Class 'Drupal\Core\Plugin\DefaultPluginManager' not found in /var/www/html/tmp/contrib/codemirror_editor/src/CodemirrorModePluginManager.php:31 Stack trace: #0 {main} thrown in /var/www/html/tmp/contrib/codemirror_editor/src/CodemirrorModePluginManager.php on line 31