Thanks DaveR. That worked.
Then, in a classic case of “Where’s my … HERE it is!”, after I stopped wrestling with it, and maybe after asking for help, the answer came to me while lying in bed:
I had been working on something where I had been trying to do a kind of free-form follow-me, moving a surface with push/pull without a path, and I had “temporarily” changed the two tools I was using alternately, Rotate and Push/pull, to be under F2 and F1. I finished my experiment, but I forgot to put things back.
Then I spent some months where I was doing all my SU on the v18 beta, so of course that was a parallel, vanilla installation and didn’t have those shortcut changes. Then when the release version of v18 came out and I installed it, those “temporary” shortcuts from the release version of v17 were automatically migrated to v18 and showed up when I started using the non-Beta version.
At least, I think that’s how it happened. In any case, it’s definitely “operator error” in not remembering that I had made that change “temporarily”.
Thanks for jumping in.