                if (tableOfContentsElem) {
                  var id = elem.getAttribute('id');
                  tocElem.querySelectorAll('a').forEach(function (elem) {
                    elem.classList.remove('active');
                  });
                  tocElem.querySelector('a[href="#' + id + '"]') ?
                    tocElem.querySelector('a[href="#' + id + '"]').classList.add('active') : null;

                  if (false === tocFolding) {
                    
                  } else {
       