code: function (toStart) {
          var self = this, rng = self.getRng(), node;
  
          // Control range on IE
          if (rng.item) {
            node = rng.item(0);
            rng = self.win.document.body.createTextRange();
            rng.moveToElementText(node);
          }
  
          rng.collapse(!!toStart);
          self.setRng(rng);
        }
docs: Collapse the selection to start or end of range.
  
  @method collapse
  @param {Boolean} toStart Optional boolean state if to collapse to end or not. Defaults to false.