I have a need to use Firefox with multiple independent sessions, due to some websites with problematic path-dependent navigation. Firefox's "Private Browsing" option seems to allow multiple windows and tabs, but they are all tied to the same session. In the current configuration, there seems to be exactly one session for all of the non-private windows and tabs, and exactly one other session for all of the private windows and tabs. This is a problem because sometimes I need a variety of windows each with a different session, and don't want to be limited to only two of them.

As an example, some airline reservation websites make it very difficult to independently browse and navigate different flight-booking searches in different windows, because the site uses cookies in a way that causes the navigation in one window to corrupt that in another window.

Are there any options in Firefox or add-ons to support this?

4 Answers 4


There is an add-on called MultiFox that does this.

OR, use the -no-remote command line switch to open another Firefox instance with its own profile if you want to run different Firefox versions simultaneously; you'll have to combine it with the -P switch specifying the alternate profile.

  • 2
    MultiFox does not support multi--process Firefox (e10s) :-(
    – DReispt
    Jan 20, 2017 at 11:14
  • 1
    @Debra would you give a example command with -no-remote?
    – alhelal
    Feb 24, 2018 at 10:02

I have not actually tried doing this yet, but possibly try using Profile Manager to set up multiple profiles, and then the ProfileSwitcher addon would help with launching them? I'm pretty sure multiple profiles are not going to share cookies, anyway. I can't speak to whether it'll do anything weird with Private Browsing, but it sounds like you're really just using Private Browsing to simulate having multiple profiles open.


As of version 53 (or earlier) Firefox Test Pilot now has support for Containers, which is basically what you are asking for (a native version of MultiFox).

Unfortunately, as best I can tell it only works for normal browsing, so your private sessions are still all lumped together.


On Linux:

firefox --profile $(mktemp -d) --private

Opens a new private browsing window with a throw-away profile. It won't interact with existing private browsing sessions.

I don't know what the equivalent of mktemp is in other operating systems.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.