I am getting this error when I am adding a field in managed fields sections in any menu.
InvalidArgumentException: Field field_test is unknown. in Drupal\Core\Entity\ContentEntityBase->getTranslatedField() (line 587 of core/lib/Drupal/Core/Entity/ContentEntityBase.php).
Drupal\Core\Entity\ContentEntityBase->get('field_test') (Line: 90)
Drupal\field_ui\Form\FieldStorageConfigEditForm->form(Array, Object) (Line: 106)
Drupal\Core\Entity\EntityForm->buildForm(Array, Object) (Line: 56)
Drupal\field_ui\Form\FieldStorageConfigEditForm->buildForm(Array, Object, 'menu_link_content.account.field_test')
call_user_func_array(Array, Array) (Line: 532)
Drupal\Core\Form\FormBuilder->retrieveForm('field_storage_config_edit_form', Object) (Line: 278)
Drupal\Core\Form\FormBuilder->buildForm(Object, Object) (Line: 73)
Drupal\Core\Controller\FormController->getContentResult(Object, Object)
call_user_func_array(Array, Array) (Line: 123)
It will throw the error
Closed: works as designed
2.15
Menu item form
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
For anyone else landing here - in my case I was missing the "bundle" entity key in the class annotations of my custom entity class... I was originally planning to write a bundleless class, but switched then to bundle-support and missed out this single line
Thank you, agoradesign, because your #3 answer helped me! And I was exactly in the same situation as you.