bug#21530: 25.0.50; tty menus disappearing

[Eli Zaretskii]

> From: Mark Oteiza <mvoteiza@udel.edu>
> Date: Thu, 24 Sep 2015 12:24:46 -0400
> 
> >> The same goes for buffers being displayed that redraw themselves
> >> periodically.
> >
> > Can you show a recipe for this starting from "emacs -Q"?
> 
> I'm not aware of a built-in mode that does this, so I'll have to concoct
> something.

It would be also interesting to see if display_mode_lines gets called
when the menu is active, and see the backtrace for that.