I didn't want to switch back to Xorg, so I found a clunky workaround:
* Select File -> Send Later (ctl-shift-enter): message is saved to Outbox.
* Select File -> Send Unsent Messages.
This method does not generate a ghost window. But wow, it's annoying. I had to remove the "Send" button from the Composition toolbar to keep me from reflexively clicking Send.
I didn't want to switch back to Xorg, so I found a clunky workaround:
* Select File -> Send Later (ctl-shift-enter): message is saved to Outbox.
* Select File -> Send Unsent Messages.
This method does not generate a ghost window. But wow, it's annoying. I had to remove the "Send" button from the Composition toolbar to keep me from reflexively clicking Send.