Running multiple versions of Firefox simultaneously
29 June, 2011 § 14 Comments
Working on a browser brings with it an interesting set of problems, one of which deals with the fact that much software research relies on looking at websites. In order to test a change, normally the browser would have to be shut down before it is recompiled. This can make reading documentation much more difficult.
Fortunately, Firefox has a way to run multiple versions of the browser at the same time. As you may (or may not) already know, there are four versions of Firefox produced by Mozilla: Release, Beta, Aurora, and Nightly.
I use one of the Release/Beta/Aurora builds for most of my browsing, while I use Nightly to test out changes that others may have checked in within the past couple of days. The fifth build of Firefox that I use is one that I compile on my local machine.
To do this, I have modified the shortcut to Firefox to add specific profiles for each build of Firefox. Simply update the shortcut target to
"../firefox.exe" -P "profileName" -no-remote
The command line switch will start Firefox using the given profile name and the -no-remote switch tells Firefox to allow multiple versions of Firefox to run simultaneously.