static <A extends Window> A disposeWindowAfter(int delay, final A w) {
  if (w != null)
    swingLater(delay, r {
      w.dispose();
    });
  ret w;
}

static <A extends Window> A disposeWindowAfter(A w, double seconds) {
  ret disposeWindowAfter(toMS_int(seconds), w);
}

static <A extends Window> A disposeWindowAfter(double seconds, A w) {
  ret disposeWindowAfter(w, seconds);
}