By default, Firefox shares one session across all browser windows that you open. Unlike Internet Explorer or Netscape who both differentiate between opening a copy of a window (thus the same session) and a new window (thus a new session). I love Firefox and use it almost exclusively, but professionally there are times when I need to have two windows open with two sessions. At first, I thought that if I simply had two profiles, that’s all I would need, but it didn’t do the trick.

Then browsing around yesterday, I discovered this little known environment variables - MOZ_NO_REMOTE - that makes this magic happen. Therefore, there’s two ingredients to getting this to work.

  1. Firefox profiles
  2. MOZ_NO_REMOTE

To make multiple profiles for Firefox, simply run “Firefox.exe -P” from a command line. This opens up the Profile Manager. Create as many profiles that you feel you’ll need independent sessions. Then create a shortcut to Firefox.exe on your desktop or quickbar for each profile you made. Right click the icon for each shortcut and open the properties window. In the Target field you need to specify which profile to use when launching Firefox like this - “F:\Program Files\Mozilla Firefox\firefox.exe” -P “ProfileA”

Then just create a new environment variable MOZ_NO_REMOTE with a value of 1.

Then you can click each Firefox icon and you’ll have a seperate session for each of your browser windows. Have fun.