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Firefox to Block Third-Party Cookies in Privacy Update

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FirefoxMozilla’s Firefox browser will have a new cookie policy when its release 22 comes out later this year. The new patch, developed by privacy advocate Jonathan Mayer, will allow first-party cookies, but block third-party cookies.

“The new cookie policy is intended to better conform to user privacy expectations and preferences,” Mayer said in an email with AdExchanger. “For my part, I share Mozilla’s enthusiasm for making Do Not Track a reality. It would provide consumer choice over third-party web tracking that is comprehensive, persistent, and polite (i.e. without technical intervention).”

The policy will be similar to that of Safari, which allows cookie permissions for first-party content and for third-party content only if it already has one cookie set, Mayer explained in a blog post about the policy.

Alex Fowler, global privacy and public policy lead for Mozilla, wrote a post on the Mozilla Privacy Blog about the update: “Many years of observing Safari’s approach to third party cookies, a rapidly expanding number of third party companies using cookies to track users, and strong user support for more control is driving our decision to move forward with this patch.”

A couple tweets from advertisers have been circulating in the media coverage of this new policy, but Mayer said he and Mozilla are open to dialogue and feedback from users and the industry.

“In my conversations with Mozillans, their thinking was guided exclusively by two touchstones,” Mayer told AdEchanger. “Does this make Firefox a better product for its users? And does this advance the web ecosystem?”

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