The only inaccuracy in the title is that it used the word "owns" as short-hand for "gets a broad license to use". Which isn't unheard of: we talk about owning a copy of a piece of software or music for example even though what we have is a perpetual and broad license to use it.

I wish the title didn't use such hyperbole, but it's closer to true than to false.

> When you upload or input information through Firefox, you hereby grant us a nonexclusive, royalty-free, worldwide license to use that information to help you navigate, experience, and interact with online content as you indicate with your use of Firefox.