Playing with libhandy, I tried the python example in source and the vala example here:
With the python exmaple, if I use Gtk.Window all is fine but with Hdy.Window, I have no round corner as promised. I have no decoration at all and the window can’t be moved.
The vala example uses Hdy.ApplicationWindow and the result is the same without changing anything in the code: no window decoration.
I use gtk-3.24 and libhandy-1.0.3. What am I doing wrong?