If a site has for example email and SMS notifier plugins, the developer needs to write the notification code twice (once for each notifier), making the system not plug-able as advertised...
I saw the notification for development in github a bit later, so I've already opened an issue on drupal.org here: https://www.drupal.org/node/2784767
On the issue thread there is some POC code.
If you look at how message_subscribe_email, and message_digest_ui modules work, they dynamically change the notifier plugin based on the user's preference (which is stored as a field on the user profile).
If a site has for example email and SMS notifier plugins, the developer needs to write the notification code twice (once for each notifier), making the system not plug-able as advertised...
I saw the notification for development in github a bit later, so I've already opened an issue on drupal.org here: https://www.drupal.org/node/2784767 On the issue thread there is some POC code.