EntityWithPluginCollectionInterface

class \Drupal\Core\Entity\EntityDisplayBase implements \Drupal\Core\Entity\Display\EntityDisplayInterface extends \Drupal\Core\Config\Entity\ConfigEntityBase
class \Drupal\Core\Entity\Entity\EntityFormDisplay implements \Drupal\Core\Entity\Display\EntityFormDisplayInterface extends \Drupal\Core\Entity\EntityDisplayBase
class \Drupal\Core\Entity\Entity\EntityViewDisplay implements \Drupal\Core\Entity\Display\EntityViewDisplayInterface extends \Drupal\Core\Entity\EntityDisplayBase

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