Thank you for the "Ctrl+Shift+M" help.
The messages move to the Last folder I move a message to.
( no folders were indicated when I chose "messages" )
Also "your email to me" disappeared before copied your email address.
Jack Stuart firstname.lastname@example.org
Oh, sorry, I was thinking of Firefox.
According to https://support.mozilla.org/kb/keyboard-shortcuts-thunderbird, Thunderbird is supposed to respond to Ctrl+Shift+M with:
"Move/Copy message to previous target folder Again"
So it sounds like that isn't the shortcut you're looking for. Is there another one in that article which might work better for you?