bug#23092: 25.0.92; Minibuffer completion fails to resize completion window if reused during same command

[N. Jackson]

At 21:04 +0200 on Tuesday 2016-03-22, Eli Zaretskii wrote:
>
>> > Press TAB repeatedly to scroll through those 50 completions.
>> >
>> > (I'm not saying this cannot or shouldn't be improved, I'm saying this
>> > is not "impossible to use".)
>> 
>> That's pretty weird, but yes, it does work (in a manner of speaking).
>
> I'm surprised you didn't know about this behavior.  It's one of the
> oldest ones I remember in Emacs, a very basic feature of displaying
> completions.

I'm not terribly surprised that I didn't know about it. Emacs is replete
with useful things that I don't know about, or have forgotten about!

In this case, back when the completions appeared in the
window-split-right, often they would all fit, so there no need to
scroll. Otherwise I relied on doing `M-x o' enough times to get to the
completion window and then worked from inside it.