docs: function(jax) {
        Explorer.RemoveHook();
        Explorer.hook = MathJax.Hub.Register.MessageHook(
            'End Math', function(message) {
              var newid = message[1].id + '-Frame';
              var math = document.getElementById(newid);
              if (jax && newid === Explorer.expanded) {
                Explorer.ActivateWalker(math, jax);
                math.focus();
                Explorer.expanded = false;
              }
            });
      }