code: function () {
              if (!el) {
                  return;
              }
  
              if (el.nodeType === NODE_TYPE.TEXT_NODE) {
                  while (el.nextSibling && el.nextSibling.nodeType === NODE_TYPE.TEXT_NODE) {
                      el.nodeValue += el.nextSibling.nodeValue;
                      el.parentNode.removeChild(el.nextSibling);
                  }
              } else {
                  dom(el.firstChild).normalizeTextNodes();
              }
              dom(el.nextSibling).normalizeTextNodes();
          }
docs: Normalizes text nodes within base element, ie. merges sibling text nodes and assures that every
  element node has only one text node.
  It should does the same as standard element.normalize, but IE implements it incorrectly.