Mozilla FakeSpot sells your private data (profile, location, browsing and search history) to advertising companies.
https://lemm.ee/comment/11216210
And when Mozilla released the Orbit AI assistant, they linked to FakeSpot for some reason...
Edit 2
The official Deepfake Detector privacy policy is missing from the FakeSpot website. This is the one Mozilla links from their extension policy.
Edit
Firefox may be bad in many ways, but the biggest alternatives are generally worse. There are some reasonably good forks like Zen and LibreWolf, but if you have the wherewithal to patch Firefox's user.js on a desktop, you'll probably be better off with a patched Firefox.
https://lemmy.world/post/4064988
https://dataswamp.org/~solene/2023-09-24-harden-firefox-with-arkenfox.html