static JFrame showFullScreen(final JComponent c) {
  ret (JFrame) swingAndWait(func {
    GraphicsDevice gd = GraphicsEnvironment.getLocalGraphicsEnvironment()
      .getDefaultScreenDevice();
    if (!gd.isFullScreenSupported())
      fail("No full-screen mode supported!");
    bool dec = JFrame.isDefaultLookAndFeelDecorated();
    if (dec)
      JFrame.setDefaultLookAndFeelDecorated(true); // XXX false);
    final new JFrame window;
    if (dec)
      JFrame.setDefaultLookAndFeelDecorated(true);
    registerEscape(window, r { window.dispose() });
    window.add(wrap(c));
    gd.setFullScreenWindow(window);
    ret window;
  });
}