Thank you for the feedback. I rebuilt emacs with the --with-x-toolkit=no option and the problem disappeared.
Op za 24 sep. 2016 om 09:32 schreef Eli Zaretskii <
eliz@gnu.org>:
> From: Tijs Mallaerts <tijs.mallaerts@gmail.com>
> Date: Fri, 23 Sep 2016 22:30:45 +0000
>
> To reproduce:
> - keep the default theme (of emacs -q) or switch to another theme with a dark background (f.ex. deeper-blue)
> - switch to the scratch buffer
> - zoom in to +3
> - hit Return a few times
>
> A slight difference of the background color is visible between the lines on which Return was hit and the blank
> lines. The first column has a different background color as well.
Not reproducible here, but my build is not a GTK+ build, and the OS is
not kubuntu.
Thanks.