Type '''about:preferences#content'''<enter> in the address bar. Across from '''fonts and colors,''' press the '''Advanced''' button. On the bottom, turn on '''Allow Web Sites To Choose Their Own.''' You can check for corrupted and duplicate fonts and other font issues: http://www.thexlab.com/faqs/multipleappsquit.html - Font Book 2.0 Help: Checking for damaged fonts http://www.creativetechs.com/iq/garbled_fonts_troubleshooting_guide.html