Comment 2 for bug 1431149

According to an archlinux forum discussion, the bug _might_ be caused by xfce4-settings. I'm not entirely sure, so I changed the affected package back to xubuntu-default-settings until I know it exactly.

Here's the post of one who testet the fix: https://bbs.archlinux.org/viewtopic.php?pid=1507949#p1507949

And there's the fix they've done:
https://projects.archlinux.org/svntogit/packages.git/commit/trunk?h=packages/xfce4-settings&id=a1a6ca07f0577a62b8e6679ee023eea774502d8e