Comment 7 for bug 505395

That video tells something important. When you click on one instance of dockbarx the picture dissappears from both. That suggest, I suppose, that the problem is somewhere within wnck and not in dockbarx. When you right-click on the group-button, wnck is called to check if the windows are maximized and/or minimized. I would guess that wnck is missing the close message from the window (perhaps because rythmbox is sending a minimize message on the same time, I dont know?). Wnck is realizing that the window is closed first when it checks the state of the window.

As a double check, does vanilla dockbar behave the same way as dockbarx?