How to find Window handle (Hwnd) of Firefox extension window

[vikram]

To get handle of any top-level or child window, use "Find window or control" dialog. FF toolbars are not windows and you cannot get handle. But they are accessible objects, and you can get IAccessible interface.

Ok, if I understood your point correctly, the toolbar XUL Window, which contains toolbar elements like toolbar buttons, and other XUL elements, is not a separate Window whose handle can be retrieved. Also, it is available as object using IAccessible interface.

Is there any way using which I can use the existing VC++ code for renedering UI in XUL window and handle its events ? Or I would be required to write that in XUL/JS and XPCOM only ?