I installed a bunch of new fonts on my Mac (running OSX) using Add Fonts through Fontbook. Now Firefox is using some weird script font for most, but not all, pages--for example, page text on www.Metafilter.com comes up in the correct font, but headlines are in script; and on Google News the page text is script but headlines are not. I checked my Firefox preferences, and the box next to "Allow pages to use their own fonts" is still checked. I'm reasonably certain that the entire interweb didn't suddenly decide to use the same unreadable script font. How can I fix this without forcing Firefox to override page fonts?