<tip type="Firefox Version 3.0.9 'Bug'"> When I view source with my brand new Firefox Version 3.0.9, it often crashes. Only when I do a print_r() actually. I found this same issue reported here: http://groups.google.com/group/mozilla.feedback.firefox/browse_thread/thread/82dec975fb9ac1b3?pli=1 including the solution, which is just to upgrade the Html Validator Add-on to the latest version. </tip>