Subject: bug#32825: 27.0.50; Deterministic window management

From: martin rudalics <[email-masked]>
Date: Thu, 08 Nov 2018 09:53:21 +0100

> I only added display-buffer-below-selected to pop-to-buffer
 > of "*Backtrace*" after display-buffer-in-previous-window,
 > and in `emacs -Q` with 3 windows where the bottom window is
 > very low, subsequent errors are displayed in different windows.

Like this

	      (pop-to-buffer
	       debugger-buffer
	       `((display-buffer-reuse-window
		  display-buffer-in-previous-window
                   display-buffer-below-selected)
		 . (,(when (and (window-live-p debugger-previous-window)
				(frame-visible-p
				 (window-frame debugger-previous-window)))
		       `(previous-window . ,debugger-previous-window)))))

I presume.  This will, in the first invocation, make a new window below
the selected one or reuse such a window because there is no previous
window.  Later on, that window gets reused here as expected,
regardless of whether the frame is wide or not.  With emacs -Q, at
least.  Maybe you have additional customizations or changes at work?

martin