bug#31695:

[Madhu <enometh@meer.net>]

The window-point jumps unexpectedly after minibuffer interaction when a
buffer is being displayed in two frames, and the frames do not have
their own minibuffers.

To reproduce: emacs -Q -D and create two frames displaying some buffer
at different points

(with-selected-frame (setq $a (make-frame '((minibuffer))))
  (let ((enable-local-variables :all))
    (view-emacs-news)
    (beginning-of-buffer)))

(with-selected-frame (setq $b (make-frame '((minibuffer))))
  (let ((enable-local-variables :all))
    (view-emacs-news)
    (end-of-buffer)))

Now select frame $b, and execute some minibuffer command:
M-: 1

The point in the window of frame $b, which was at the bottom now jumps
to the top of the buffer.  (This corresponds with the point in the
buffer in the other frame where it is displayed.

In GNU Emacs 27.0.50
Repository revision: d2d35febf28632aafb087952fd4c07c2899e21c5
Windowing system distributor 'The X.Org Foundation', version 11.0.11004000

Configured using:
 'configure -C --without-all --with-xml2 --with-dbus --with-m17n-flt
 --with-libotf --with-xft --without-x-toolkit
 --without-toolkit-scroll-bars'

Configured features:
DBUS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT OLDXMENU X11
[snip]