bug#70038: 29.3.50; Shift up/down in buffer with images on M-x other-window with some fonts

[martin rudalics via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

 > There's one more aspect of this that bothers me: when we resize the
 > mini-window, we set the frame's frozen_window_starts flag, but we seem
 > to never reset it.
 >
 > Martin, can you help out here?  I don't see shrink_mini_window being
 > called with non-zero DELTA anywhere, including when the mini-window is
 > exited and is resized to its normal one-line height.  Instead, this
 > resizing is performed by restore_window_configuration, called from
 > read_minibuf, but I don't see FRAME_WINDOWS_FROZEN being reset
 > anywhere there.  I don't think it's correct for us to leave the
 > frame's frozen_window_starts flag set forever once it was raised,

Just for the record: Here I once used a version of shrink_mini_window
that went as

/** Shrink mini-window W to its minimum height.  */
void
shrink_mini_window (struct window *w)
{
   /* Just attempt to shrink it to zero, grow_mini_window makes sure it
      does not get to small.  */
   FRAME_WINDOWS_FROZEN (WINDOW_XFRAME (w)) = false;
   grow_mini_window (w, -WINDOW_PIXEL_HEIGHT (w));
}

where grow_mini_window took care of the rest.  But I don't call
shrink_mini_window any more and so the flag remains stuck here as well.

 > so I
 > guess we should do something in minibuffer_unwind to reset that flag?

Would that be sufficient?  Don't we freeze also when resizing the echo
area?

martin