All classes that implement MessageNotifierInterface in Message Notify 8
- class \Drupal\message_digest\Plugin\Notifier\Digest
- class \Drupal\message_digest\Plugin\Notifier\DigestBase implements ContainerFactoryPluginInterface, DigestInterface
- class \Drupal\message_notify\Plugin\Notifier\Email
- class \Drupal\message_notify\Plugin\Notifier\MessageNotifierBase implements MessageNotifierInterface
- class \Drupal\message_notify\Plugin\Notifier\Sms
- class \Drupal\message_notify_test\Plugin\Notifier\MessageNotifierTest