🇵🇱Poland @adr_p

Rerolled against rc19 and:

• Replaced empty($entity_id) calls (that don't work for entities with machine names) with $entity->isNew().
• On the widget configuration form, dynamically hide "Keep or delete unreferenced..." if the "Allow users to delete existing..." checkbox is unchecked.
• Don't display the "Keep or delete..." setting in the widget configuration summary if configured not to allow deleting existing entities.

adr_p → created an issue.

Attaching a patch.

adr_p → created an issue.