Not working with SDDM

[Joeviocoe]

I am running KUbuntu 16.04 using the sddm display manager.
The build, setup and configuration look good, from your testing procedure in the faq... however the desktop windows do not seem to be using the split virtual monitors.

• ldd $(which xrandr)

    linux-vdso.so.1 =>  (0x00007ffea3bea000)
    libXrandr.so.2 => /usr/local/lib/libXrandr.so.2 (0x00007f2921188000)
    libX11.so.6 => /usr/lib/x86_64-linux-gnu/libX11.so.6 (0x00007f2920e48000)
    libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f2920b38000)
    libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f2920768000)
    libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f2920560000)
    libxcb.so.1 => /usr/lib/x86_64-linux-gnu/libxcb.so.1 (0x00007f2920338000)
    /lib64/ld-linux-x86-64.so.2 (0x000055e7b221a000)
    libXau.so.6 => /usr/lib/x86_64-linux-gnu/libXau.so.6 (0x00007f2920130000)
    libXdmcp.so.6 => /usr/lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007f291ff28000)

The xrandr command shows virtual monitors ~1 ~2 and ~3 just as expected.

1. How would I be able to tell if an application, or display manager, is properly using the xrandr configuration?
2. Do I need to install a new display manager? Or just run a wrapper of some kind?

Ultimately I wish to split my Maxtor triplehead2go And have all windows maximize to those virtual monitors. Also, virtualbox needs to be able to detect these as separate so the virtual machines will see them as 3 separate monitors. It looks like virtualbox does indeed see all virtual monitors, but can't go full screen unless the host dm can constrain the boundaries to the virtual monitors.

I had this working using fakexinerama when I was on Kubuntu 14.04 and would like to know if the same functionality can be expected with fakexrandr.

Thanks.

[phillipberndt]

It shouldn't matter whether you're using SDDM or another login manager. The relevant question is which window manager you're using. KDE, probably?!

I strongly suspect that this is related to #16, the missing libxcb support: All applications that use the newer libxcb instead of the old libXlib do currently not work with fakexrandr.