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Does Firefox still store the PREF cookie and if so how can I delete it?

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  • 1 has this problem
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  • Last reply by cor-el

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I heard about this on an EFF video and I've tried sqlite to open cookies.sqlite and delete it from there but I can't seem to get into the firle. Nothing shows up on the cookie manager and I've disabled 'Block reported attack sites and 'Block web forgeries' but I just wanted to know if Firefox still stores this persistent Google cookie as a matter of policy because it is a unique identifier and can be used for surveillance, as a I understand it.

I heard about this on an EFF video and I've tried sqlite to open cookies.sqlite and delete it from there but I can't seem to get into the firle. Nothing shows up on the cookie manager and I've disabled 'Block reported attack sites and 'Block web forgeries' but I just wanted to know if Firefox still stores this persistent Google cookie as a matter of policy because it is a unique identifier and can be used for surveillance, as a I understand it.

All Replies (2)

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There are usually two PREF cookies (Firefox 27 and later):

  • A cookie set by Google when Firefox downloads the latest list of malware/phishing sites
  • A cookie set by Google when you use search (maybe also other services)

When you clear or block website cookies, that definitely takes care of the second PREF cookie, but may not have any effect on the first one.

Since these cookies are separate, Google should not be able to use the first one for tracking what happens in normal browsing. However, if EFF's testing shows otherwise, that would be concerning. Where is the video -- can you post the URL?

Also, cookies.sqlite is a database file. In order to look inside it, you can use the SQLite Manager extension: https://addons.mozilla.org/firefox/addon/sqlite-manager/

Or if you don't my losing all your existing cookies, you can just delete cookies.sqlite. Please make sure Firefox has closed fully and finished its shutdown cleanup before deleting any settings files.

Modified by jscher2000 - Support Volunteer

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