В коментах к аддону Self-Destructing Cookies на addons.mozilla.org посмотри инструкцию от Skepp Tikal

DarkMasterW
SDC is outstanding, but it cannot block the google.com PREF cookie. However, I used a method to remove and defeat the google.com PREF cookie, which prevents the PREF cookie from repeatedly and persistently reinstalling after each time a user removes it.

The google.com PREF cookie did not return after I removed the cookie and took the following additional steps:

1) Open Firefox/Preferences/Privacy/Show Cookies/Cookies and remove all google.com cookies.

2) In Firefox/Preferences/Security, deselect "Block reported attack site" and "Block reported web forgeries".

3) When a user selects those settings, the google.com PREF cookie will reinstall in the browser after the user removes the PREF cookie.

4) Quit and close Firefox. This is a necessary step. Otherwise the remaining steps will fail to prevent the googl.com PREF cookie from reinstalling in your browser after you remove the cookie.

5) Open ~/Library/Application Support/Firefox/Profiles/[current Firefox profile folder name such as 9skvsz0g.default-1402623486951, or whatever is the folder name]/cookies.sqlite

6) Drag the "cookies.sqlite" file to the Trash folder. Every conventional cookie in your browser is in that file. You will lose all of those cookies until such time your browser installs them again, except the google.com PREF cookie will not return.

7) Restart Firefox.

8) Firefox automatically will generate in the Profile Folder a new "cookies.sqlite" file in place of the file you put in the Trash folder. The file will not contain the PREF cookie.

9) Before you delete the "cookie.sqlite" file that is in the Trash folder, you can prove that the "cookie.sqlite" file contains the google.com PREF cookie.

10) All *.sqlite files are text files. Right click the "cookies.sqlite" file that is the the Trash folder and chose "Open with TextEdit.app" or any other text editor application.

11) Read the text in the "cookies.sqlite" file.

12) The text "google.com PREFID" will be present somewhere in the long list of characters in the file.

13) The new "cookies.sqlite" file that replaced the offending file will not have the google.com PREF cookie in it.

14) The google.com PREF cookie will not return to the "cookies.sqlite" file unless you select "Block reported attack site" and "Block reported web forgeries" in Firefox/Preferences/Security.

Это cookie от SafeBrowsing (блокировщика опасных сайтов по данным Google).

https://bugzilla.mozilla.org/show_bug.cgi?id=1026538
https://bugzilla.mozilla.org/show_bug.cgi?id=1008706

Отредактировано Deleter (13-03-2015 00:04:58)