FDroid currently has 383 open MRs to their main repo. Most are app updates or new apps waitikng to be added to the repo.

That is really quite a work queue for the volunteer maintainers.

If you're looking for places you could contriubute in OSS, this could be one, very meaningful way to do so.

#FDroid

Here's a good place to start if you want to understand what helping to test apps would mean:
https://gitlab.com/fdroid/wiki/-/wikis/Internal/Reviewing-new-apps
Reviewing new apps · Wiki · F-Droid / wiki · GitLab

Wiki for all things free software, Android, and of course F-Droid

GitLab