Re my question above....I've actually just managed to load one of the websites I'm having trouble with, but the account Login button which appears on that particular webpage won't work when I click on it, so I can't log in! I've also tried resetting the page zoom and made sure that the font settings are as suggested in this thread, but still the button won't work (and the page takes forever to load) http://support.mozilla.com/oc/questions/791520#answer-145734