I'm a very active volunteer and can always use the help of folks that have tech experience already. We get lots of student volunteers that require a lot of work to shepherd. As such, issues tend to be claimed pretty fast but also medium sized ones don't always get through the finish line.
Anyway, if you're seriously willing to commit some time you can tag me on their slack/github (@raybb). I'm currently doing a lot of performance related work (primarily migrating their codebase to fastapi) and I could use help but don't always open issues for it because sometimes guiding a non-experienced person is more work than just doing it.
There's also quite some design work going on to move things into the modern age and more reliable. One small thing that comes to mind is getting rid of jquery where it's used casually (not where a library depends on it). We have a few files like that.
Happy to chat more with anyone who is seriously willing to spend time to tackle medium sized issues with a few rounds of feedback!
I made a good-faith effort at searching the site for anything requesting volunteer work, and came up empty. Got a pointer? What are they looking for?