Yeah, its not that the entire website won’t work, it’ll be some vital part of it.
Various Federal and State and Local government websites will have a captcha that just doesn’t load, or have a search map or filter system that bugs out and doesn’t work.
Happens with a good number of slapdash apartment websites too, and some smaller businesses.
Theres a few things I have to regularly use that just do not actually work on Firefox so I have to keep Chrome around… =(
Again though, sometimes you can get them to work by just using a browser spoofing addon to tell the website that you are actually Chrome. Which is insane because… basically that means theyre just intentionally making Firefox not work even though it does.