bug#69983: Use category for display-buffer-alist

[Eli Zaretskii <eliz@gnu.org>]

> Date: Thu, 11 Apr 2024 11:16:25 +0200
> Cc: 69983@debbugs.gnu.org
> From: martin rudalics <rudalics@gmx.at>
> 
>  > In any case, if you are suggesting to change the "random" place where
>  > warnings are displayed, we should first discuss that, because your
>  > assertion that no one will dislike the change sounds very much like
>  > famous last words to me, so to speak ;-)
> 
> This part
> 
> +				    '(display-buffer--maybe-at-bottom
> +				      (window-height . (lambda (window)
> +					(fit-window-to-buffer window 10)))
> 
> would hard-code a new preference which might cause problems indeed.  But
> the subsequent
> 
> +				      (category . warning)))))
> 
> would allow users to customize the display of warnings via
> 'display-buffer-alist' and cannot harm otherwise.

I understand, and might even agree.  But (a) as I wrote elsewhere in
this thread, I don't think display-buffer-alist should be the
advertised means of controlling display of warnings, and (b) I happen
to think that display-buffer-alist is so complex and arcane that
asking users to use it as the means of customizing such simple
settings is not very user-friendly, to say the least, especially when
we change existing behavior (which is likely to cause users to want to
get the previous behavior back).

This is why I suggested to discuss the proposed new behavior.  It is
possible that we will all agree that it is superior to the old one, in
which case the above-mentioned considerations will not apply.  But if
not, then the default should reflect what we think most users will
want, and how to implement that takes a back seat.