I was trying to install Firefox 3.0b5 in OS X with Firefox 2 installed and it didn’t open both at the same time after some look around this was what I had to do:
- Download the latest version of Firefox 3;
- Install the application somewhere but your applications folder (ex. Desktop);
- Rename the application of Firefox to something else (ex. Firefox3);
- Copy the application to the Applications folder;
- Open a terminal and run the following commands:
- The profile manger will appear, create a new profile and press “Start Firefox”;
- Open Firefox3, choose the new profile and browse!