At 18:08 29/05/2020 +0100, I wrote:
... I suspect that this message from me will also appear in the archive but not be received by *some* mailing list subscribers, whose mail providers simply obey the standards and reject my messages as forwarded by the list.
Aha! I'm delighted to find that I was wrong. My btinternet.com mail has been provided for some time by Yahoo, but was changed a few days ago and is no longer. My new mail arrangements no longer show the problem. But M. Gauthier is still out of luck - and it's the fault of the LibreOffice Users list, not his yahoo.com.