Are you referring to Google Keyboard? If that's the case, I'm afraid this isn't the right forum to ask that question.

It’s only a problem in firefox, so that’s not really helpful— it works literally everywhere else

I wasn't able to find any other report about this. Have you tried reinstalling Firefox?

Yes, I did and it didn’t help. I am literally typing this now on some kind of keyboard that seems to be inherent to firefox, as the only one I have installed is gboard

I’m not even able to access the keyboard option from this page— I’ve been struggling with this for a week

I try to replicate the issue on Firefox for iOS 106.1 on iOS 15.6.1 and Gboard version 2.3.19 but it wasn't successful. Have you tried checking if your Gboard app need an update?

I have removed it and reinstalled it twice now. It works everywhere else

I'm afraid I'm running out of ideas here. You may want to file a bug report if you believe that it's a bug from our end. Here's an article that should help you do it -> File a bug report or feature request for Mozilla products.

Thanks, I want to, and definitely will!