This company sells some JS libraries to track users through aggressive fingerprinting; their global database of fingerprinted users is huge by now.
The "demo" in the official website is actually a way to keep fingerprinting visitors and improve the database. The JS libraries used to be on f.fingerprintjs.com; however, after a few years, they have just switched to g.fingerprintjs.com (they probably noticed that people were starting to block the old host).
That being said, every subdomain such as *.fingerprintjs.com should be blocked.
, one of the 3p sites in uBO is dropboxfingerprintjs.com. But I just block it at the DNS level with PiHole; not sure if that is available to others, though. Also, FWIW, openfpcdn.io is fingerprintjs's CDN. I've seen it in the wild a couple of times.