bug#8355: 24.0.50; Boxes in mode-line and scrolling

[Eli Zaretskii]

> From: Antoine Levitt <antoine.levitt@gmail.com>
> Cc: larsi@gnus.org, 8355@debbugs.gnu.org
> Date: Mon, 14 Dec 2020 20:02:22 +0100
> 
> 14 December 2020 19:25 +01, Eli Zaretskii:
> > Thanks, please try the latest master branch.  I hope I improved the
> > situation some more.
> 
> Oh wow, that's awesome! I'll try it out some more but it seems that the
> problem is mostly gone (ie it still happens sometimes, but pretty
> rarely).

AFAICT, it generally happens when you have a continued line around the
place where the new window-start should be.  Then Emacs will move
window-start one or more screen lines to start after a newline, and
you have a mismatch going back.