You are a Firefox developer, right? Not a mere user.
Firefox takes a totally different approach to blocking cookies than IE/Chrome/Safari.
Firefox blocks the setting and transmission of cookies by/to 3rd parties.
The other browsers just block the setting of new cookies by 3rd parties.
An example of what this means:
A Safari or Chrome/IE user who has turned on 3rd party cookie blocking visits facebook.com in a 1st party manner (by visiting the facebook home page). He/she then visits CNN, where facebook is present as a 3rd party (via the like button). Even though that user has opted to block 3rd party cookies, their stored facebook cookies will be transmitted to facebook when it acts as a 3rd party, because the cookies were first set as a 1st party.
In comparison, when a Firefox user who has turned on 3rd party cookie blocking visits CNN, facebook has no idea who they are.
No one is visiting doubleclick.net as a 1st party, which means if Google turned on the Chrome/Safari style 3rd party cookie blocking, it wouldn't be able to track users for behavioral advertising (interestingly, Facebook could still do so). Were this to happen, I guess Google could always move away from using doubleclick.net and put everything under the google.com domain, which would get around this.
Mozilla's method of 3rd party cookie blocking does indeed cause collateral damage, which AFAIK, is why Mozilla hasn't turned it on.
Google doesn't have the same excuse for allowing 3rd party cookies, since Apple users don't suffer broken sites when they browse. (If the Flash fiasco has shown us anything, it is that websites will bend to Apple's will, and change whatever breaks in order to allow Apple users to visit their sites).
If third party cookies were eliminated entirely, the companies currently using them could get the same effects by using technology that is more than 10 years old and proven to work. When Firefox, Mozilla, Safari, IE, and Chrome change their cookie implementations to block 3rd party cookies, they are wasting millions of development dollars and hours and they have no effect on the end result -- ubiquitous tracking will continue.
Regulating the technology is, and always will be, a waste of time. If people don't want the tracking done, they need to outlaw it, regardless of technology implementation.
Well, sure, but that's not relevant for purposes of this discussion. ;) The fact that I use the browser and turn off third-party cookies is the relevant part.
> The other browsers just block the setting of new cookies
> by 3rd parties.
Ah, interesting. That significantly reduces the value of that setting, as you point out.
I suppose we could look into blocking the setting of such cookies by default and only the sending when the pref is flipped. I'll file a bug, thanks!
Firefox takes a totally different approach to blocking cookies than IE/Chrome/Safari.
Firefox blocks the setting and transmission of cookies by/to 3rd parties.
The other browsers just block the setting of new cookies by 3rd parties.
An example of what this means:
A Safari or Chrome/IE user who has turned on 3rd party cookie blocking visits facebook.com in a 1st party manner (by visiting the facebook home page). He/she then visits CNN, where facebook is present as a 3rd party (via the like button). Even though that user has opted to block 3rd party cookies, their stored facebook cookies will be transmitted to facebook when it acts as a 3rd party, because the cookies were first set as a 1st party.
In comparison, when a Firefox user who has turned on 3rd party cookie blocking visits CNN, facebook has no idea who they are.
No one is visiting doubleclick.net as a 1st party, which means if Google turned on the Chrome/Safari style 3rd party cookie blocking, it wouldn't be able to track users for behavioral advertising (interestingly, Facebook could still do so). Were this to happen, I guess Google could always move away from using doubleclick.net and put everything under the google.com domain, which would get around this.
Mozilla's method of 3rd party cookie blocking does indeed cause collateral damage, which AFAIK, is why Mozilla hasn't turned it on.
Google doesn't have the same excuse for allowing 3rd party cookies, since Apple users don't suffer broken sites when they browse. (If the Flash fiasco has shown us anything, it is that websites will bend to Apple's will, and change whatever breaks in order to allow Apple users to visit their sites).