1449492 - When selecting "Never remember history", cookies are shared with all the windows, including the private windows

Status: RESOLVED INVALID

(Firefox :: Private Browsing, defect)

Description

[djc]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:59.0) Gecko/20100101 Firefox/59.0
Build ID: 20180315233128

Steps to reproduce:

1. Open "Preferences/Privacy & Security" and select "Firefox will Never remember history".
2. Restart Firefox
3. Open a "New Window", then log in to a website with your login and password, like https://www.google.com/ for example.
4. Open a "New Private Window", then go to https://www.google.com/.
5. You are already logged to Google in the private window.


Actual results:

When "Never remember history" is enabled, logging in to a website in a default window also make you logged on a private window. This means the cookies are shared between default windows and private windows.


Expected results:

When "Remember history" is selected instead of "Never remember history", cookies are not shared between default windows and private windows. I'd expect that when "Never remember history" the behavior remains the same.

I suspect this may be related to how the "Always use private browsing mode" setting works. This setting can be manually set when "Use custom history settings for history" is selected and is enabled as part of "Never remember history" .

As far I understand it, when "Always use private browsing mode" is enabled, there is no difference between default windows and private windows and they all share the same cookies.

I think this is an issue, because this behavior defeats the purpose of private windows and decreases privacy for the users who care the most about privacy and selected "Never remember history".

Comment 1

[Justin [:JW_SoftvisionQA]]

I can reproduce this issue on my machine Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:61.0) Gecko/20100101 Firefox/61.0

Remember history - Requires me to sign in on firefox & private browsers. 

Never Remember history - Requires me to sign in on firefox browser & keeps me signed on on a private browser.

Comment 2

[Johann Hofmann [:johannh]]

Never Remember History == Always use private browsing

That is why opening a "private window" opens a regular window in that mode.