@ Martin Jelen
Thank you very much for the hint, it helps, now the left upper corner displays Ubuntu desktop and behaves like it.
Not sure when the background is black, here it's a transparent conky "own_window_transparent yes", admitting the whole desktop cube is transparent.
@ Martin Jelen transparent yes", admitting the whole desktop cube is transparent.
Thank you very much for the hint, it helps, now the left upper corner displays Ubuntu desktop and behaves like it.
Not sure when the background is black, here it's a transparent conky "own_window_
For me "own_window_type override" solves the bug.