When viewing a message body, in the little pop-up with the airmail-like border, I would like buttons to move to the previous or next message.

It's a nuisance to have to close the window and then remember which message I was just looking at to select the next one.

Also, I noticed that Michael McLennan had wished for a Delete button in that window (Wish #15); that wish is marked as granted, but I don't see that button now.