The issue for me is Windows 7. No browser that I know of (not Firefox, Edge, Chrome, or Brave) has a version on Windows 7 that supports the required useless new features that Discourse is demanding. The need for a new computer comes from the fact that most computers more than a few years old aren’t compatible with Windows 11. A last-ditch last hope is Supermium, an obscure fork of the Chromium platform that runs on older versions of Windows.
Regarding Firefox, I’m on the ESR program and have the latest update, but for Windows 7 those are security updates; they don’t bring any new functionality.
In my view this an absolutely asinine move by Discourse which is very disruptive to users on older platforms and brings very minimal benefits (like, none at all that I can see).