function showOneOffOverlay(player, className, overlayJsx, align) {
  // Delete existing:
  OVERLAY_DATA.overlays = OVERLAY_DATA.overlays.filter((x) => x.name !== OVERLAY_NAME_ONE_OFF);
  // Create new one:
  OVERLAY_DATA.overlays.push({
    name: OVERLAY_NAME_ONE_OFF,
    class: className,
    content: ReactDOMServer.renderToStaticMarkup(overlayJsx),
    start: 'immediate',
    align: align,
  });
  // Display it:
  player.overlay(OVERLAY_DATA);
}
Wrapper to hide away the complexity of adding dynamic content, which the
plugin currently does not support. To change the 'content' of an overlay,
we need to re-create the entire array.
This wrapper ensures the PERMANENT_OVERLAYS (and potentially other overlays)
don't get lost.