Fatal error: Uncaught Error: Class 'Drupal\Core\Field\WidgetBase' not found in /var/www/html/tmp/contrib/codemirror_editor/src/Plugin/Field/FieldWidget/CodeMirrorEditorWidget.php:22 Stack trace: #0 {main} thrown in /var/www/html/tmp/contrib/codemirror_editor/src/Plugin/Field/FieldWidget/CodeMirrorEditorWidget.php on line 22