Andreas F.X. Siegert wrote:
Thanks for looking! So this is an XFCE sillyness only, other compositing WMs don't suffer from it?
I think it's to do with the X11 compositing manager, even if the window manager is not intervening. The property needed (_NET_WM_WINDOW_OPACITY) is standardised (I think), it's just that it doesn't appear in the current doco on standard WM properties (ie. <http://standards.freedesktop.org/wm-spec/wm-spec-1.4.html>), and it should help with all the compositing WMs. Graeme Gill.