>Some websites already detect ad blocker extensions and instruct users to disable them. //
Indeed but ad blocking and user tracking are different orders of need for the advertisers. Advertisers still want access to FF users even if they can't track them. Currently with browser fingerprinting "don't track" is probably just another high-value data point to make the fingerprinting more successful.
>Probably less than 1% of Firefox users know what a User-Agent string is. //
How many people who've watched a ripped DVD know about DVDCSS. Firefox could just go the IE route and spoof by default (alright they don't quite spoof, just jam everyone else's UA strings in to their own). I see no reason that browser fingerprint spoofing (to coin a phrase) can't be as democratised as adblocking. How many adblock users know how it works?
>Which toolbar button is that?
"Hello" button that kept re-appearing had Telefonica's name with it; perhaps FF didn't view that as advertising but I imagine the market rate for "we'll put a button that links to your name in the browser of every Firefox user and when they remove it we'll put it right back" has got to be in the 10s of millions of USD.
Indeed but ad blocking and user tracking are different orders of need for the advertisers. Advertisers still want access to FF users even if they can't track them. Currently with browser fingerprinting "don't track" is probably just another high-value data point to make the fingerprinting more successful.
>Probably less than 1% of Firefox users know what a User-Agent string is. //
How many people who've watched a ripped DVD know about DVDCSS. Firefox could just go the IE route and spoof by default (alright they don't quite spoof, just jam everyone else's UA strings in to their own). I see no reason that browser fingerprint spoofing (to coin a phrase) can't be as democratised as adblocking. How many adblock users know how it works?
>Which toolbar button is that?
"Hello" button that kept re-appearing had Telefonica's name with it; perhaps FF didn't view that as advertising but I imagine the market rate for "we'll put a button that links to your name in the browser of every Firefox user and when they remove it we'll put it right back" has got to be in the 10s of millions of USD.