I could beat it by using a different browser (e.g. chrome vs firefox) on my machine.
- Group1: Chrome, Chromium, Opera, ...
- Group2: Firefox, Tor Browser, ...
- Group3: on iOS every browser is based on Safari
- ...
Though with a backend you could track users switching among Chrome and Firefox by misusing WebRTC to leak the private IP ( https://www.perfect-privacy.com/webrtc-leaktest/ ). If the switching between browsers happens in a short period of time, the public + private IP is a pretty solid guess. If you observe and store this connection once you can always track the user switching among the two browsers.