Ouch. I'm pretty sure that here in Germany they could be sued for that. Regarding privacy law there we have a general consensus that out-out is too weak in almost all cases. You need opt-in, or in some cases double opt-in.

Also, I wonder why Mozilla is playing the game that way. Aren't they afraid that actions like this may damage their reputation?

On the other hand, this may simply be the continuation of their "pragmatic" policy that led them into feeding Google Analytics with their sites and making Google the default search engine (instead of privacy-friendly alternatives).

There's also a Medium post that went out with the Hardware Report that details more about the process behind it. https://medium.com/mozilla-tech/https-medium-com-mozilla-tec...

Firefox would also definitely not be the first piece of software to run in Germany that has opt-out instead of opt-in. Most software does it that way and usually much sneakier than Firefox.