[Users] Strange behavior when deleting an opened message gets deleted

[anton92 at gmx.ru]

When a message is open in its own window and I delete it, the
window is not closed. Instead, its contents are emptied and I get
the message "Message has been deleted or moved to another folder".

Is this behavior normal?
What I would expect is that, upon deleting the message (with <del>),
that window should close automatically.

Moreover, I have noticed that due to this strange behavior another
problem is likely to result: since the focus is silently shifted to the
background window, containing the listing of the messages, the user
may keep pressing <del> in the attempt to make the foreground empty
window disappear, or may press <del> more than once, to make sure that
the message was actually delete. All the while, each time <del> is
pressed, a message gets deleted in the background window, unbeknown to
the user.
This is a non-trivial issue.