1551280 - All private windows are using the same privateBrowsingId, sharing cookies and other site data

Status: NEW

(Firefox :: Private Browsing, defect, P3)

Description

[evit]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:66.0) Gecko/20100101 Firefox/66.0

Steps to reproduce:

1. Open a new private window.
2. Log in to a website (e.g. gmail).
3. Open another private window, either from the regular window or from the previously opened private one.

Actual results:

You are logged in into the website in the new private window. Moreover, if you log in in the last open private window and then switch to a previously opened private window - you will be recognized in that window too!

Expected results:

I expect not to be recognized / tracked across private windows.

Comment 1

[evit]

Well, this seems like expected behavior :( How confusing though - I can have multiple private windows, but all of them are bound to the same session. So all but the first one aren't actually "private". Sorry for bothering the community about it (I did search the KB before opening the bug, honest!).

Comment 2

[:Gijs (he/him)]

This is better off not being a hidden bug.

Comment 3

[Johann Hofmann [:johannh]]

Baku, I know we talked about this recently, do we have a bug for de-duplicating private browsing OAs so that each window gets its own? If so, we could dupe this one. Otherwise we might want to re-open it.

Comment 4

[Andrea Marchesini [:baku]]

We don't have an existing bug. We can reopen this one.

Comment 5

[BugBot [:suhaib / :marco/ :calixte]]

The priority flag is not set for this bug.
:groovecoder, could you have a look please?

For more information, please visit auto_nag documentation.

Comment 7

[pwosj]

I expect not to be recognized / tracked across private windows.

Safari users also expect the same. There, every private tab is isolated. https://bugzilla.mozilla.org/show_bug.cgi?id=1694026
Window level isolation is also acceptable (to me personally ofc).