Odd, it was 'true' for me, and I have all the privacy stuff in there set to the most private of settings. There was one section in there with an option labeled

Odd, it was 'true' for me, and I have all the privacy stuff in there set to the most private of settings. There was one section in there with an option labeled: > Allow websites to perform privacy-preserving ad measurement Strangely, though, it was already unchecked, and at any rate, greyed out so I couldn't toggle it. Toggling that about:config value didn't change the state of that checkbox. I also found another about:config pref called "dom.origin-trials.private-attribution.state" (set to zero for me); I wonder if that has anything to do with it.