gtk:window-default-widget (object)

object -- a gtk:window widget
widget -- a gtk:widget object to be the default widget, or nil to unset the default widget for the toplevel

The accessor for the default-widget slot of the gtk:window class gets or sets the default widget for the window. Pass the nil value to unset the default widget.

The default widget is the widget that is activated when the user presses the Enter key in a dialog for example.