code: function filterStylesheetsWithSameHref(sheets) {
  	let hrefs = [];
  	return sheets.filter(sheet => {
  		if (!sheet.href) {
  			// include sheets without `href`
  			return true;
  		}
  		// if `href` is present, ensure they are not duplicates
  		if (hrefs.includes(sheet.href)) {
  			return false;
  		}
  		hrefs.push(sheet.href);
  		return true;
  	});
  }
docs: Exclude any duplicate `stylesheets`, that share the same `href`
  
  @param {Array<Object>} sheets stylesheets
  @returns {Array<Object>}