I don't think any of this will work correctly under the existing hildon-desktop due to the way that GtkHeaderBar is drawn (it ends up under the status area iirc). You can force it to render the window manager title bar and it should display correctly at the top and draw the GtkHeaderBar underneath, but you'd lose lots of space. The real purpose of this test was to try getting the stacked window concept working without hildon-desktop and without relying on directly using X11 functions. Sorry if the explanation is a little confusing. It's been a while since I started this.