I recommend the User-Agent Switcher and Manager Firefox addon for those struggling with some sites.
You can also report a broken site to Mozilla directly via the browser menu.
There was another (third-party?) page where you could report websites but I forgot its url.
Dazed_Confused@lemmy.world 1 month ago
I used this extension on edge to view one particular site (although I never managed to make it auto load on that page, but meh). As I said firefox seems to work without it for some reason.