> Does it hide GPU name that is exposed via WebGL/WebGPU? Does it hide internal IP address, available via WebRTC?

My GPU is reported as simply "Mozilla" by https://abrahamjuliot.github.io/creepjs/.

The number of cores is also set to 4 for everyone using this config and/or Tor.

> It's not going to work, because the fingerprinting script can be (and is often served) from first-party domain.

This may be true, but allowed third party content makes it trivially easy for Google and others to follow people around the Internet through fonts delivery systems among others.