The Firefox Extension for this site has been updated, and is available here. If you have the old one installed, it *should* automatically update itself within a few days. However, it's a two click install, so why wait? (It may never happen!)
Click 1: Go to the Mozilla Developer site Click 2: Click on the name of the plugin (Murky.org).
Wait a bit. Look in the search box in the top right for the little purple 'M'.