docs: function(d) {
        if (d.isCaching && d.removeEventListener) {
          d.removeEventListener('DOMAttrModified', mutationWrapper, true);
          d.removeEventListener('DOMNodeInserted', mutationWrapper, true);
          d.removeEventListener('DOMNodeRemoved',  mutationWrapper, true);
          d.isCaching = false;
        }
      }