Running Multiple FireFox Versions Simultaneously

While testing a small FireFox plugin in both 0.9.3 and PR-1 I noticed a small oddity. Open 0.9.3, leaving this window open try and open an instance of PR-1. When both windows are open click on the Help menu, now select ‘About Mozilla FireFox’. Both windows are version 0.9.3.

I’m note sure if this is a bug with FireFox opening new windows with a ‘getobject’ call rather than a ‘create object’ call (that is a serious over simplification! :)) and having an instance of the already running version returned or if it’s something weird with my settings under the ‘tabbed browser settings’ plugin but it is odd and it caught me for a couple of minutes as I wondered how my plugin was already installed.