The release candidate of Firefox 3.6 is finally out, but if you install it, any extension that still hasn’t been updated to support the latest release is going to error out or just not work.
What you’ll need to do is use the new compatibility hack to get it working. And before you start talking about nightly tester tools and other extensions to force compatibility, some of us don’t want to bloat up Firefox with yet another extension, and prefer the about:config hack instead.
You can click the link to read the full description, or just create a new boolean key with this name, and value set to false:
The new version of Firefox adds a bunch of features like Personas themes that can switch without restarting the browser, notifications for ancient, insecure versions of Flash, and a bunch of extra stuff that will speed up the browser.