May break some sites, though. http://www.bit-tech.net/news/bits/2015/11/04/firefox-42-tracking-protection/1
"...Tracking Protection automagically blocks adverts..." What sorcery is this? Wonder if they'll eventually have a "paid whitelist" sort of thing similar to what AdBlock did/does...
"...Tracking Protection automagically blocks adverts, analytics, and social sharing buttons which are known to track a user's behaviour..." I don't think it is all adverts.