Run Firefox 2 and 3 simultaneously

Despite the vast improvements in Firefox 3, I’ve still been using Firefox 2 because of the instability of Firebug 1.2 (beta versions). The final Firebug 1.2 version was released recently, and many of the issues have been resolved, however, I thought I’d post the steps I took to run both Firefox versions together:


Firefox 2
Firefox 3


If you already have one version installed, just install the other version, making sure to choose the Custom installation option. This will allow you to install the files into a different directory.

For example, if you already have Firefox 3 installed in C:\Program Files\Mozilla Firefox, install Firefox 2 in C:\Program Files\Mozilla Firefox 2. The rest of this post assumes that you are installing Firefox 2…modify as necessary.

Manage Profiles

From the command line, run the Profile Manager to manage your Firefox profiles:

"C:\Program Files\Mozilla Firefox 2\firefox.exe" -profilemanager

Create a new Profile, firefox2 for example, and then exit the Profile Manager.

Update Firefox Shortcuts

Mofify the Target value on your shortcuts to Firefox. Right-click on the short-cut and select Properties.

For the Firefox 2 shortcut, on the Shortcut tab, enter:

"C:\Program Files\Mozilla Firefox 2\firefox.exe" -no-remote -p firefox2

Do the same for the Firefox 3 shortcut, with the following:

"C:\Program Files\Mozilla Firefox\firefox.exe" -no-remote -p default


Install Firebug 1.05 for Firefox 2. You should now be able to run both Firefox 2 and 3 simultaneously. If you already have Firefox 2 are installing Firefox 3, just change the paths/profile names mentioned above to fit your situation.

Caution: If you already have one version installed, use the Firefox Profile associated with it, otherwise you might loose your settings.

Scroll to Top