bug#51210: Customizable other-window-for-scrolling

[Eli Zaretskii <eliz@gnu.org>]

> From: Juri Linkov <juri@linkov.net>
> Cc: rudalics@gmx.at,  51210@debbugs.gnu.org
> Date: Wed, 12 Jan 2022 21:45:00 +0200
> 
> >> > This is age-old behavior.  Why change it because you happen to dislike
> >> > it?
> >> 
> >> The problem is that with its current implementation, it's unusable:
> >> when the window height is 75 lines, then typing M-<end> leaves
> >> half-screen empty.
> >
> > If you start typing at the end of the buffer, the half-empty window
> > will immediately make sense.
> 
> You can't start typing because it's in another window.

Fortunately, Emacs has this "C-x o" command that fixes that small
problem.

> > Are you using scroll-conservatively, perhaps?  If so, I can understand
> > why you don't like this behavior.  But that's your subjective opinion,
> > and I see no reason to change this by default.
> 
> This problem is reproducible in emacs -Q:

I think you misunderstood me.  I was trying to explain to myself why
you don't like the default behavior.

> >> But fortunately this can be fixed since Emacs 28 introduced a new key
> >> C-M-S-l to recenter the other window, so it's now easy to type it
> >> when the user needs to recenter the other window.
> >
> > Great.
> 
> So everyone who wants to recenter, can type: 'M-<end> M-C-S-l'.

I object to changing this behavior by default.