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Stop cross tab/window cookie sharing in private mode

  • 2 replies
  • 1 has this problem
  • 1 view
  • Last reply by cor-el

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When visiting a site (eg. retailer) in private mode, the site still retains my complete viewed items history in that private mode session. So if a purchase is being made in that session, the complete history can still be collected. Containers, from my understanding and trials, whilst stopping cross-site cookie sharing, still do not achieve the above. Even more so, it seems logical to assume that in Private mode the cookie jar is shared by all sites --and shared!-- since Containers are not designed/ allowed in this mode.

The only browser with "true" private mode seems to be Safari, from which I have a hard time migrating, considering this lapse in privacy configuration.

What am I missing?

When visiting a site (eg. retailer) in private mode, the site still retains my complete viewed items history in that private mode session. So if a purchase is being made in that session, the complete history can still be collected. Containers, from my understanding and trials, whilst stopping cross-site cookie sharing, still do not achieve the above. Even more so, it seems logical to assume that in Private mode the cookie jar is shared by all sites --and shared!-- since Containers are not designed/ allowed in this mode. The only browser with "true" private mode seems to be Safari, from which I have a hard time migrating, considering this lapse in privacy configuration. What am I missing?

All Replies (2)

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There are only two cookie jars, one for normal mode and one for Private Browsing mode. Containers only work in normal mode and not in PB mode and can be used to keep cookies separate between containers.

See:

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This means that in Private Browsing mode you have no options to keep cookies separated with standard Firefox. You can search the AMO website (https://addons.mozilla.org/firefox/addon) for a cookie manager extension that works in Private Browsing mode.