Mozilla has just deleted the following:
“Does Firefox sell your personal data?”
“Nope. Never have, never will. And we protect you from many of the advertisers who do. Firefox products are designed to protect your privacy. That’s a promise. "
Source: Lundke journal.
Of course not, but it’s the principle of the thing. I don’t want my data to be in anyone’s hand, if I can help it, but certainly not used for ads, regardless of whether I can actually see the ads or not.