Font Book is lousy at correcting its database when fonts are removed from the system. Try these steps.
Restart your Mac and immediately hold down the Shift key when you hear the startup chime to boot into Safe Mode. Keep holding the Shift key until you see a progress bar towards the bottom of the screen. You can let go of the Shift key at that point.
OS X asks you to log in (you will get this screen on a Safe Mode boot even if your Mac is set to automatically log in). Let the Mac finish booting to the desktop and then restart normally. This will clear Font Book's database and the cache files of the user account you logged into in Safe Mode.
Next, close all running applications. From an administrator account, open the Terminal app and enter the following command. You can also copy/paste it from here into the Terminal window:
sudo atsutil databases -remove
Terminal will then ask for your admin password. As you type, it will not show anything, so be sure to enter it correctly.
This removes all font cache files. Both for the system and the current user font cache files. After running the command, close Terminal and immediately restart your Mac.
Thank you so very much, Kurt, for replying. I can't tell you how I appreciate it.
I followed your instructions and it worked partially in that the italics are gone now and from a quick test round it seems in all cases, so fora, shops, blogs that were all in italics are now normal again, including the text I am typing right now. However, the bold text issue persists.
This is what I know now:
- There were web pages where text was in italics but not bold that are now displaying correctly again.
- There were web pages where all text was bold but not in italics and they are still bold (about 70% of my forums and quite a few newspapers, including the New York Times and the Washington Post, to give just a few examples - and by the way, not all is bold in the newspapers, but the main articles all are).
Anything else I could try maybe?
To me this is just very weird, but I have browsed this forum a bit and understand that you are an expert on fonts and their workings, so if you can't come up with a solution, then I won't look any further and re-install Snow Leopard, although I hate to think of the work involved...
At this point, the most likely cause would be bad fonts. Free fonts are the number one source of font problems. They're free for a reason.
Do this. Create two new folders on the desktop. Call one Library, and the other User. Move all of the fonts in the /Library/Fonts/ folder into the Library folder on the desktop. Move all of the fonts in the /Library/Fonts/ folder of your user account into the User folder. The only active fonts on the system now will be those in the /System/Library/Fonts/ folder.
Follow the instructions at the bottom of Font Management in OS X to restore just the fonts from your Snow Leopard DVD. You only need to do the /Library/Fonts/ folder, but it wouldn't hurt anything to do the System folder's fonts, too.
Lastly, repeat the steps above to clear Font Book's database and all font caches.
I may receive some form of compensation, financial or otherwise, from my recommendation or link.
Thank you so much for that. Easy steps to follow, a brilliant application and all is well again. I can't tell you how relieved I am. You sir, are a wizard!
Can I bother you with one last question? I have some Hebrew and Greek fonts that I use for my work. They come from reliable sources, I've had them forever so they're safe. Can I just drag them into the /Library/fonts folder to install them, or is it better to use font book?