Well, I did the emergency restore and it's working again. I guess something just got corrupted somehow. That did lose my most recent session, but before the restore I had done an export, which worked despite the data being "invisible", so on a re-import everything's back to normal.

EDIT: Wait, no it's not. I see URLs in the saved data that don't appear when I search their titles in the box. Does the saved data include more than is displayed?