First-Party Isolation (restricts cookies & data to the first party domain)

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First-Party Isolation (restricts cookies & data to the first party domain)

Post by smed79 » Thu Nov 23, 2017 11:48 pm

Firefox has silently embarked another feature borrowed from the browser Tor in version 55 which was deployed last August: First Party Isolation (FPI). FPI works by separating cookies by domain. This is important because most online advertisers place a cookie on the user's computer for each site visited by the user and then they upload an ad.

When FPI is enabled, the ad tracking tool can not see all the cookies it has posted on that user's PC, but only the cookie created for the domain that the user is viewing.


- ... n-firefox/
- ... isolation/

/!\ This feature is not enabled by default because it can cause some user login persistence issues.
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