message: Watches subtree for changes to handle overflow
diff: @@ -81,12 +81,19 @@ export default class Overlay extends PureComponent {
  document.body.addEventListener('mousewheel', this.debouncedPositionOverlay);
  this.positionOverlay();
  +
  + // Re-position the overlay if anything in the subtree changes
  + this.observer = new MutationObserver(this.positionOverlay);
  + this.observer.observe(this.wrapper, { childList: true, subtree: true });
  }
  componentWillUnmount() {
  this.el.parentNode.removeChild(this.el);
  +
  window.removeEventListener('resize', this.debouncedPositionOverlay);
  document.body.removeEventListener('mousewheel', this.debouncedPositionOverlay);
  +
  + this.observer.disconnect();
  }
  alignToEl = (el) => {
  