I tried it in Firefox and Tor, and got the same identifier for both, but in both cases it said, "This is your identifier. It is unique among [####] tests so far

I tried it in Firefox and Tor, and got the same identifier for both, but in both cases it said, "This is your identifier. It is unique among [####] tests so far." But.. it wasn't unique for the second browser I tried. And they'd be coming from different IPs, so it wouldn't have any way to know both were coming from the same person, aside from the fingerprinting itself...