docs: function (selector, hash) {
      this.actionQueue.push(this.webdriverClient.element.bind(this.webdriverClient, selector));
      this.actionQueue.push(this.webdriverClient.displayed.bind(this.webdriverClient, selector));
      this.actionQueue.push(this._visibleCb.bind(this, selector, hash));
      return this;
    }