I use Awesome VM with KDE and it works rather good up until Kubuntu 14.10. Now I tried the upgrade to Kubuntu 15.04 and the KDE background picture lays over the wibox (the control bar of Awesome WM) on the first virtual screen. I cannot see the wibox, but when I change the virtual screen with [Mod4]+[2], I have a black background and see only Awesome WM and no background image.

Is there a way to get the Plasma Session to be in the very background?

You can see virtual screen 1 on the left and virtual screen 2 on the right. You can see the Plasma 5 background image on the left, it is gone on the right. The Awesome WM wibox is not shown on virtual screen 1 but the space is reserved by the windows.

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