code: function Postmate(_ref2) {
      var _ref2$container = _ref2.container,
          container = _ref2$container === void 0 ? typeof container !== 'undefined' ? container : document.body : _ref2$container,
          model = _ref2.model,
          url = _ref2.url,
          _ref2$classListArray = _ref2.classListArray,
          classListArray = _ref2$classListArray === void 0 ? [] : _ref2$classListArray;
      // eslint-disable-line no-undef
      this.parent = window;
      this.frame = document.createElement('iframe');
      this.frame.classList.add.apply(this.frame.classList, classListArray);
      container.appendChild(this.frame);
      this.child = this.frame.contentWindow || this.frame.contentDocument.parentWindow;
      this.model = model || {};
      return this.sendHandshake(url);
    }
docs: eslint-disable-line no-undef Internet Explorer craps itself 
  Sets options related to the Parent
  @param {Object} object The element to inject the frame into, and the url
  @return {Promise}