Firefox 22 will block third-party cookies
Jonathan Mayer, a researcher at Stanford, has contributed a patch for Firefox that will block third-party cookies from installing on the user's browser. The patch is set to be incorporated into Firefox 22. For some sense of timing on the project, Firefox 19 was released on Tuesday.
With the patch, Firefox would allow all cookies from sites that a user actively visits, but would block cookies from third-party sites if a user has not visited that cookie's origin site. Advertisers generally place third-party cookies and can collect data about a user across several websites with them. This is used to serve more targeted ads or refine where an advertising firm should spend its money.
Blocking third-party cookies would not be new or unheard of among browsers; Apple's Safari already rejects cookies from third-parties. In a blog post on Friday, Mayer called the Firefox patch, “a slightly relaxed version of the Safari policy.” Chrome allows all cookies, and Internet Explorer blocks some third-party cookies, although not all.
