After today’s system update, my fonts suddenly went wacky. They got big, fuzzy and ugly. Going on memory, from like a gadzillion years ago, I remembered that there was an Appearance item in Systems Preferences to deal with this. Sure enough I had to reset my Font Smoothing Style to “Standard - best for CRT”. What I’d totally forgotten though is that you have to log out and log back in for the change to take effect. So here’s my reminder for anyone else affected: Don’t Forget to Log Out & Back In.
Hope this helps.