bug#39379: 27.0.60; Fix for #38457 broke ido-vertical-mode

[Eli Zaretskii]

> Date: Sun, 02 Feb 2020 20:06:16 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 39379@debbugs.gnu.org, dgutov@yandex.ru
> 
> > I think this could be a bug in the display engine, related to resizing
> > the mini-window when an after-string that includes many newlines is
> > put at EOB.  Let me look into it.
> 
> Looks like my guess was correct.  I'll try to devise a solution.

Workaround: set ido-max-prospects to 7 or less.