any typos in XHTML (when served as XML) will result in the yellow-and-red screen of death in Firefox. Or, say, using && in your javascript. Yes, that does it.

any typos in XHTML (when served as XML) will result in the yellow-and-red screen of death in Firefox. Or, say, using && in your javascript. Yes, that does it. I have the 30 minutes of wasted time a week ago to prove it. Here's the "solution", just so you can see how elegant it is. You have to escape it like this: <script type="text/javascript"> /* <![CDATA[ */ if (var1 && var2) blah blah; /* ]]> */ </script> Or just use AND I suppose, forgot if it's got some weird precedence difference or something.