_NET_WM_WINDOW_OPACITY doesn't work with xcompmgr

[Dmitry Baryshev]

Hi.

I have KUbuntu Gutsy with Composite extension enabled. xcompmgr works
fine, it draws shadows as expected and so on.

But in my GUI application it is not possible to set transparency of my
window manually. If I use _NET_WM_WINDOW_OPACITY or setWindowOpacity()
from Qt4 (which does the same), nothing happens. Window does not
change its transparency. transset works fine.

How to use _NET_WM_WINDOW_OPACITY with xcompmgr?

Thanks!

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