Is your issue confined to FTM, or does it manifest when you try to log in to other Websites that use Safari's AutoFill?
Good thought.....but I have very few places I use autofill, and haven't been to any for a while, so I can't confirm one way or the other.
However...........
To restore this functionality, while logged out of FTM go to Safari -> Preferences -> AutoFill and click the Edit... button next to User names and passwords.
When I went here, I found that the global autofill checkbox "User names and passwords" was unchecked. I rechecked it and am back in business without having to delete and redo.
Even my dog is shaking her head at this one.
Thanks all....your time is appreciated.
ryck