Back on the old blog I posted about how I run multiple version / profile pairs of Firefox on OS X using a mix of shell script and AppleScript with a dash of yak shaving.

I still use this all the time, but it continues to be a problem for others so here's an update on the various third-party options out there for making this easier:

• Multi-Firefox - a launcher with a Gui that people seem to like, currently OS X only.
• Install All Firefox - a shell script installer and manager, also for OS X
• Windows-specific instructions, a bit older but still completely relevant. I like in particular the trick of creating shortcuts for each profile.
• when I was using Linux on the desktop ( for years ) running Minefield and release, I just used bash aliases?

There are in fact a LOT of blog posts about this, mainly targeted at the power user / web developer audience. Mozilla has not made any changes in this area for years, although it has been discussed a lot. As a Product Manager for Firefox Developer Tools I care a lot about this issue, and as Dave mentions here making it easier for developers to use the latest tools is a very high priority for us in 2014.

http://canuckistani.ca/running-multiple-versions-of-firefox-update/