Run Firefox 3, Firefox 4 and Firefox 5 at the same time on Mac OS X

by AJ on June 27, 2011

This supercedes the post I did a few months ago on how you can run Firefox 3 and Firefox 4 at the same time on Mac OS X. This time you can run Firefox 3, Firefox 4 and Firefox 5 at the same time.

Here’s how:
1) Download the new Firefox 4

2) Create a new folder on your desktop. Let’s name it “Firefox 5”

3) Double-click the installation file. Usually “Firefox 5.0.dmg“. You will see something like below…

4) Drag the Firefox icon to your newly created folder “Firefox 5“. Note: Not on “that” Applications folder.

5) Select the Firefox icon, hit “Enter” and rename it to “Firefox 5“. Why? You need to distinguish them quickly when you’re opening them up. Especially if you will use it on your dock together with Firefox 3 and Firefox 4. See below…

6) Now let’s create a new Profile specifically for Firefox 5. Open your “Apple Terminal” (You can find it in Applications >> Utilities >> Terminal). Upon opening, it should look similar to this…

a) Let’s type in the following below:
cd /Applications/Firefox.app/Contents/MacOS/

b) Hit “Enter”
c) Then type:
./firefox-bin -ProfileManager

d) Hit “Enter” again. Your Firefox Profile Manager should now open and you should see something like below…

e) Let’s create a new profile. Click “Create Profile…” >> “Continue” >> On the “Enter new profile name:” type in “Firefox 5” (I used AJ Firefox 5 just to be consistent with my old ones) >> Finally, hit “Done” >> Un-tick/Un-check “Don’t ask at startup”

7) Finally, you can open up your new Firefox 5 by selecting your newly created Firefox 5 profile >> “Start Firefox”

8) You’re done. Enjoy!

It’s really nice to see Firefox 3, Firefox 4 and Firefox 5 run at the same time