@Schouten_B And now that you mention it, if you look you will find I mention the "only for specific providers" matter later in this same thread. In my view, this makes the implementation *worse* than Google's. Google's implementation is open to all, whereas Firefox's is limited to partners whose identities *Firefox does not disclose*, at least in its public messaging about the feature. Practically better maybe, but morally worse.
@Schouten_B I do not agree that this system is "completely different" from Google's. It is hard to tell because Firefox has disclosed less information than Google has (perhaps there is another document with technical details somewhere else) but my initial read of the information I have is that Google's "Ad Lab"/"Ad Privacy" comprises three reporting features and Firefox has implemented a specific one of them wholesale, apparently (per their statement) with an eye to formalizing it as a standard.