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Does firefox prevent sites and javascript code from accessing existing cookies and web sites data when browsing in Private Browsing mode?

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  • Last reply by cor-el

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In Private Browsing mode, the cookies, web site data and history is not maintained. However what about the existing data in firefox cache, like cookies and website cache data, i.e. data and trace that has been collected prior to starting the Private Browsing Mode. Is that shared with the websites too? Is there a mechanism where websites and their javascript code can get access to this data, even in Private Mode?

In Private Browsing mode, the cookies, web site data and history is not maintained. However what about the existing data in firefox cache, like cookies and website cache data, i.e. data and trace that has been collected prior to starting the Private Browsing Mode. Is that shared with the websites too? Is there a mechanism where websites and their javascript code can get access to this data, even in Private Mode?

Chosen solution

No. Private Browsing mode only means that no personal data is saved to the profile folder. In PB mode a separate in memory cookie jar is used, so websites can't access cookies created during a regular session. In all other ways there is no difference in handling cookies and their allow/block exceptions.

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Chosen Solution

No. Private Browsing mode only means that no personal data is saved to the profile folder. In PB mode a separate in memory cookie jar is used, so websites can't access cookies created during a regular session. In all other ways there is no difference in handling cookies and their allow/block exceptions.