Unable to log in with Firefox 82

I’m using Fedora linux and just updated my browser to Firefox 82 and now I can’t log in to my HA web interface. The HA installation is HassOS 4.15.
It loads the login page but when I try to log in it jumps to a page with just a blue bar on top and a string saying ‘Initializing’. Then it just sits there doing nothing. Is there a log file somewhere that I can look at to figure out what is going on?

If I downgrade my browser to Firefox 81 it loads just fine, but I would like to stay on the latest released version.

Does anyone have a solution for this?