Subject: Re: bug#18912: 24.4; mode-line corruption on graphical frames in dual-headed display

From: Eli Zaretskii <[email-masked]>
Date: Mon, 03 Nov 2014 05:34:46 +0200

> Date: Sun, 02 Nov 2014 19:49:50 -0200
> From: Bruno Félix Rezende Ribeiro <[email-masked]>
> CC: [email-masked]
> 
> What about implementing a global variable
> 'refresh-mode-line-after-scroll' which when set to 't' repaints the
> mode-line after any scroll operation?

Unnecessary redrawing causes unpleasant flickering that people
rightfully complain about.

Emacs never writes buffer contents where the mode line should be, so
this problem could only happen if Emacs for some reason becomes
confused about the window dimensions.  The result could be a variety
of display problems, not just what you see.

Are you willing to debug this problem on your machine using GDB?  If
so, I might come up with some instructions.