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

From: Stefan Monnier <[email-masked]>
Date: Fri, 31 Oct 2014 16:30:18 -0400

> In this setup GNU Emacs corrupts the mode-line (a graphical glitch)
> drawing over it the buffer's line that would otherwise be below it.

My guess is that it's a bug in the X11 acceleration code for your
graphics card.  At least, that was the conclusion the last time this
came up, IIRC.

        Stefan