static int moveToTopCenter_inset = 20;

static <A extends Component> A moveToTopCenter(A c) {
  Window w = getWindow(c);
  if (w != null) {
    centerFrame(w);
    Rectangle r = usableWindowArea();
    w.setLocation(w.getX(), r.y+moveToTopCenter_inset);
  }
  ret c;
}