Bingo! Thanks @Tester. Problem solved.
I had a hunch that it was something simple which I was overlooking. No car I’ve owned previously had a window lockout switch, and I somehow hadn’t noticed that button - have only had the car a short time - & didn’t get the owners manual. Duhhhh.
Thanks also @Cougar, and @Mustangman for the good education. I was preparing to dive deeper into this if necessary, but I didn’t want to start hunting for a bad wire in the door jamb, or poking around on the motor contacts, until all the simpler things were eliminated.