I understand why I don't want Apple Mail to move my deleted messages to [GMail]/Trash.  So I don't do that.

But in my other IMAP servers, Apple Mail seems to be able to support 'Undo Delete Message', so that if I am too quick on the draw deleting a message out of my InBox, Command-Z will bring it back (there is actually a history, I can undelete some number of messages, not just the last).  This feature does not work for my GMail IMAP account, but I can't tell why.

I tried the setting of _not_ moving deleted messages to the Trash at all.  This results in the message being marked deleted in my InBox, but as soon as the InBox gets sync-ed, it is also immediately expunged.  So even with Show Deleted Messages on, I don't see the deleted message, and Mail does not offer an Undo option to bring it back.

My next thought was to create a 'Deleted' label (which Mail would treat as a folder) and tell Mail to move deleted messages to that 'folder'.  It seemed to me, this should be just like other IMAP servers now.  When I deleted a message from my InBox, Mail would 'move' it to the Deleted folder, GMail would remove the InBox label and add the Deleted label.  My hope was that this would make the Undo Deleted Message action work in Mail, but, no joy...

Any suggestions?