It might have been your DNS that was identified? It depends on whether you enabled proxy DNS for SOCKS5.
For best fingerprinting protection, use either:
- Mullvad Browser with a VPN (prefer Mullvad VPN)
- Tor Browser
Avoid using Tor with a normal browser because you will stick out like a sore thumb.
That is not what I was referring to. DoH is easy to access in the settings, but with a SOCKS5 proxy you want DNS from the provider to avoid fingerprinting of your location by using a network or DoH provider, which may be a geographically closer server because of your host IP.
Under about:config, change “network.proxy.socks5_remote_dns” to true.
I don’t know definitively why they were fingerprinted to there local city, this is just a theoretical reason.