I'm surprised nobody has reported this yet; at least I wasn't able to find it.
If you were wondering why some nostriches choose Firefox-based browsers—for instance because Firefox currently has stable proxy connection support compared to Chromium-based browsers.
https://issues.chromium.org/issues/492069660
It's not that obvious it's broken. Most websites work fine because they don't create so many WS connections.
It's also sad that none of the browsers currently support the UDP part of the Socks5 protocol. It should be useful for HTTP/3.