Gtk.Window.prototype.set_transient_for

function set_transient_for(parent:Gtk.Window):void {
    // Gjs wrapper for gtk_window_set_transient_for()
}

Dialog windows should be set transient for the main application window they were spawned from. This allows <link linkend="gtk-X11-arch">window managers</link> to e.g. keep the dialog on top of the main window, or center the dialog over the main window. Gtk.new_with_buttons and other convenience functions in GTK+ will sometimes call Gtk.Window.prototype.set_transient_for on your behalf.

Passing null for parent unsets the current transient window.

On Windows, this function puts the child window on top of the parent, much as the window manager would have done on X.