Privacy

Those sites aren't really useful. If your threat model requires "hiding your fingerprint" you can use Tor Browser.

I also use Librewolf, most settings are preconfigured.

I use librewolf, and even with max privacy settings and anti-fingerprinting, it still said I had a semi-unique fingerprint. Turns out that the site wasn't built to handle the anti-fingerprinting system which will give false and randomized information about your computer to websites. So you're probably fine, but you can always use librewolf if you want more privacy