code: func (v *MenuButton) GetPopover() *Popover {
  	c := C.gtk_menu_button_get_popover(v.native())
  	if c == nil {
  		return nil
  	}
  	return wrapPopover(glib.Take(unsafe.Pointer(c)))
  }
docs: // GetPopover is a wrapper around gtk_menu_button_get_popover().