bug#14582: 24.3.50.1; Strange overlay behavior, when window-start is inside an overlay.

[Eli Zaretskii]

> From: Michael Heerdegen <michael_heerdegen@web.de>
> Cc: larsi@gnus.org,  esabof@gmail.com,  14582@debbugs.gnu.org
> Date: Wed, 02 Feb 2022 05:02:41 +0100
> 
> Is there a third alternative, a hook or something that could be used, to
> perform this task automatically?

It cannot be a hook, because from the display engine POV nothing
happened that could trigger a hook.  The visible contents of the
window is different, that's all.

So it shouldn't be a hook, it should be a buffer-local variable that
would change how redisplay behaves in these cases.  I will see what
can be done about it.