Let's say I'm using Firefox and I get a kernel panic, which just happened again. After I restart the Mac, I restart Firefox, which immediately tries to the page that caused the kernel panic -- thus causing another kernel panic ad infinitum. How do I break this cycle?

In the past when I restarted Firefox I frantically try to close windows and tabs and quit of force-quit Firefox, using my mouse buttons and command-W and command-Q. If I'm fast enough, I can keep Firefox from reloading the troublesome sites, but often it takes a couple attempts, and it's such a dumb, tedious way to solve the problem. I also have multiple tabs open at once whenever I'm on the internet, so I'm not always certain which tab, i.e. web site, is causing the kernel panic. When I figure it out, I make a mental note, which is now turning into a text document with a list of web sites I can't visit. Some of these web sites had been useful.

Quite frustrating, really. One of the few drawbacks of using an old system.

This is Firefox 39.0.3, but it happened to earlier versions the past few years. Years ago, I'd never even seen a kernel panic. My research from previous kernel panics suggest that there's something wrong with my imac's graphics drivers, something about how they interact with web sites via Firefox.

I can't fix that, but does anyone have any idea how to keep Firefox from reloading past pages as soon as it restarts? In fact, in the Prefs, I even have "clear history after quitting Firefox" selected but it doesn't work in this circumstance. There should be an option "after a Mac crash, do not load previous session." This is a fairly serious problem.