
Calls always notify. So the last option is what you are looking for. Maybe we should make it more clear that this is about chat messages only.
We could add a section title like 'Chat notifications', which would allow us to remove the 'notify' word from the three options below and would make it clear that it'd be only for the chat.

Label strings:
https://github.com/nextcloud/spreed/blob/c2334265152980954f6b397c1e91166f92195d09/js/views/roomlistview.js#L114-L116
Not sure if a caption is already implemented, but try it.
Hint, when modifying the handlebar templates, you need to run make compile-handlebars-templates
Ok, I'm on it!
If you can't find samples anywhere, use the left sidebar in the settings section as template, since that has headers.
Here's how it looks:
