Goodness gracious, I came to the right place. You are a sharpshooter.
2022-03-01, 19:31, Kevin J. McCarthy:
I believe this behavior is from libidn2.
This was exactly right.Incidentally, my sendmail program (msmtp) seemed to refuse to override the envelope's From header, regardless of the options I threw at it. Meanwhile, unsetting idb_encode seems to have done the trick.
Thank you!
