A new bundled addon is coming for 11.alpha5 called "site_messaging".

This addon will replace the weirdness (and the broken) site messaging configuration options under Admin Zone > Setup > Configuration > Messages.

Once installed, you can manage your pinned global messages through a new UI under Admin Zone > Setup > Site messaging. This will allow you to add, edit, and delete messages individually instead of having to use JSON for multiple messages.

A new feature is that you can also specify page-link filters in addition to usergroup filters. So you can define specific pages on which to run a message.

A new tutorial for using this addon is up at https://composr.app/docs/tut-site-messaging.htm .

This addon will install itself only when upgrading to 11.alpha5. Skipping over this upgrade will result in not having this addon installed by default. So once 11.alpha5 is out, it is strongly advised to upgrade to it first before any future v11 versions.