We should say something like "Note: Theseus Extension Update Required" or something like that, so it doesn't look like a new feature we're listing.  We used a "Note:" prefix on the earlier 10.6 warnings.

But I wonder if this sets a bad precedent to put extension update warnings in these notifications.  If Emmet or Key Remapper or some other popular extensions needs an update, will we list it too?  Feels kinda like favoritism if not, but if we start listing them all it will pollute the upgrade notification.  Maybe best to leave notices like this in the release notes and/or brackets-dev?