Come to think of it I have experienced from time to time that a bit “wiggling” — by moving between fields already filled in — sometimes is needed in admin menus before the save button becomes active. A glitch I haven’t bothered to report, as it’s not affecting daily use… guess first thing would be for someone to spend time on narrowing it to a few reproducible steps to be able to file a useful GitHub issue.
Great that you finally got email working though! 