I find that it's currently very easy to miss invite notifications to join a new Team. (I personally had never used cryptpad notifications before, and had barely noticed their existence.)
I think the issue is that AFAICT the invite only exists in the notification (my intuition would instead be that notifications should be notifying about something that can also be found "directly" by navigating to a relevant UI panel).
Additionally to the current notification list, could there be an additional "pending Team invites" panel that would appear in the Teams page (when first navigating to /teams/)?
This is the place someone is most likely to go to after being told that they have been "added" to a new Team.
