document.querySelector('.navframe').addEventListener('load', function() { // Get the current page URL without the suffix after # var currentPageURL = window.location.href.split('#')[0]; // Get all anchor tags var as = document.querySelector('.navframe').contentWindow.document.body.querySelectorAll('a'); for (const a of as) { if (a.href) { var href = a.href.split('#')[0]; // find the one with the current url if (href === currentPageURL) { a.style.fontStyle = 'italic'; // open all detail tags above the current var el = a.parentNode.closest('details'); while (el) { el.open = true; el = el.parentNode.closest('details'); } // seeing as we found the link we were looking for, stop break; } } } });