Works on Fedora 25, Debian 8, LinuxMint 17, Unbuntu 15.02.

I have to suspect xfce4 is doing something to my display.
I am running MX Linux 16.1 (based on Debian 8).
It's a new install, I know exactly what I have configured in it.
xfce4 is new to me.

I will try a different window manager.