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Privacy/Incognito cookies shared with non private window

  • 2 replies
  • 0 have this problem
  • 2 views
  • Last reply by T.Kallup

T.Kallup
T.Kallup
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So I'm running a Firefox Developer Edition (I do this to have my work related stuff separated from my personal stuff).

I was testing A/B testing software on our website, when I noticed that Private window shared some of the non-Private window cookies.

I have made a recording of the issue in action. On the left side is a private mode window (notice the missing extensions), on the right side is a normal window. They are both open on the same page and first thing to notice, is when I refresh the private window, cookies in inspector "flash" in both windows, indicating that there are changes. After that, I'm interested in two cookies: "gbuuid" and "growthBookVariants", it seems like they are shared and when I refresh one windows, it's value is "synced" to the second window.

Now this is annoying, as I have to clear those cookies to test if I get a different variant. When a colleague tested it on Windows, it didn't happen so maybe it's something with my settings/extensions? I attached my privacy settings, but when I fiddled with those, nothing seemed to change.

So I'm running a Firefox Developer Edition (I do this to have my work related stuff separated from my personal stuff). I was testing A/B testing software on our website, when I noticed that Private window shared some of the non-Private window cookies. I have made a [https://drive.google.com/file/d/1TmwXjrIWwG90dh61UG_SOLKa8LFrtm3j/view recording of the issue] in action. On the left side is a private mode window (notice the missing extensions), on the right side is a normal window. They are both open on the same page and first thing to notice, is when I refresh the private window, cookies in inspector "flash" in both windows, indicating that there are changes. After that, I'm interested in two cookies: "gbuuid" and "growthBookVariants", it seems like they are shared and when I refresh one windows, it's value is "synced" to the second window. Now this is annoying, as I have to clear those cookies to test if I get a different variant. When a colleague tested it on Windows, it didn't happen so maybe it's something with my settings/extensions? I attached my privacy settings, but when I fiddled with those, nothing seemed to change.
Attached screenshots

Modified by T.Kallup

All Replies (2)

zeroknight
zeroknight
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Does it still happen in a new profile? An easy way to test a new profile is to install Nightly and see if it happens there or refresh your existing profile.

T.Kallup
T.Kallup Question owner
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zeroknight napsal(a)
Does it still happen in a new profile? An easy way to test a new profile is to install Nightly and see if it happens there or refresh your existing profile.

Yes it does. I went to about:profiles, created new profiles and clicked the `Launch profile in new browser` button. Confirmed that I was not logged in and no addons were installed and the cookies issue still happens. Visiting the site sets cookies, opening private window with the same site updates the cookies in both windows and removing it in one window removes it from both.