I've searched high and low for the answer to this but no luck. This may appear at first glance to be a simple request but what I actually want seems to be a bit tricky.
I am running multiple instances of Firefox on my Mac OS X Lion machine (using the shell script at http://mabouali.wordpress.com/2012/03/03/opening-multiple-instances-of-firefox/ to do so). It works great, BUT the new instance automatically loads everything that is open in the current (first) instance. I'd like to know if there is some modifier that can be applied, that would override this behavior ONLY for this launch of FireFox. A single-use suppression, if you will.
To be clear, Safe Mode will not do, I do not want to disable this behavior in preferences, and I'm not looking for something where I would have to launch FireFox, make a tweak, then restart again. I need a way to disable this behavior at any arbitrary moment when I decide to launch FireFox.
Anyone got any clever ideas?