A user on a site of mine found out the hard way, and has disabled it.  There probably isn't anything you can do, but just wanted to give you guys a heads up if someone else has 'crashing' problems when they're using the editor.  I myself have had the Google and Alexa toolbars installed, and no such issues have ever occured.  Furl must be doing something wacky with it's pop up blocker.