code: function getElmId(elm) {
  	if (!elm.getAttribute('id')) {
  		return;
  	}
  	let doc = (elm.getRootNode && elm.getRootNode()) || document;
  	const id = '#' + escapeSelector(elm.getAttribute('id') || '');
  	if (
  		// Don't include youtube's uid values, they change	on reload
  		!id.match(/player_uid_/) &&
  		// Don't include IDs that occur more then once on the page
  		doc.querySelectorAll(id).length === 1
  	) {
  		return id;
  	}
  }
docs: Get ID selector