(this._indicatorsElement) {\n      const indicators = [].slice.call(this._indicatorsElement.querySelectorAll(SELECTOR_ACTIVE))\n      $(indicators).removeClass(CLASS_NAME_ACTIVE)\n\n      const nextIndicator = this._indicatorsElement.children[\n        this._getItemIndex(element)\n      ]\n\n      if (nextIndicator) {\n        $(nextIndicator).addClass(CLASS_NAME_ACTIVE)\n      }\n    }\n  }\n\n  _updateInterval() {\n    const element = this._activeElement || this._element.querySelector(SELECTOR_ACTIVE_ITEM)\n\n  ...