Every time I change anything in Font Book (enable, disable fonts for example) all my international default fonts in FireFox and in Safari get so messed up, that it's hard to read sometimes. The default fonts suddenly become substituted by other fonts. I tried completely reinstalling the system fonts folder (fetched it from MAC OSX installation CD) but no result. I tried disabling all the custom fonts, and then enabling again the ones I need - didn't help.
Every time this happens, I need to restart my Mac in Safe Mode, and restart again, so that it deletes it's font cache. Then all is Ok, until the next time I do anything in Font book.
This is really annoying, please help!