bug#25054: 25.1; bury-buffer makes bad choice of next buffer

[Francesco Potortì]

> > I wonder why the default was set to t.  Do you know if there is a simple
> > explanation?
>
>To return to a previous window configuration without having to restore
>it explicitly.  Consider simultaneous editing of two portions of the
>same buffer after C-x 2.  If one of the windows is temporarily used for
>showing things like help, info or completions, quitting that window
>should implicitly restore previous buffer and location.
>
>The thread on Bug#20861 contains an explanation why your buffer "c" (one
>that was never shown before in the window you created via C-x 4 b) is
>unveiled there by ‘bury-buffer’.  Maybe Jürgen's solution could be
>improved by switching to an already visible buffer (like "c") only after
>all other possibilities have been exhausted.  Patches welcome ;-)

Ok, after setting switch-to-visible-buffer to nil it got better, but it
is not how it was with Emacs 22 (okay, I have emerged from a long time
tunnel).

My main problem is with the *mail* buffer (I have mail-user-agent set to
'sendmail-user-agent).  After I send mail, the *mail* buffer is buried,
but after a while it pops up.  I would expect that, being buried, it is
the last choice as the other buffer.  Apparently it is not.

I don't know why, and I have not time to investigate now, sorry.  But if
you care to suggest some ideas, I may find the time sooner or later :)