Why did js stop seeing the object after building with gulp?

Question

HTML

The problem is that after assembling all the js files, it does not see the declared slider and does not allow accessing it. Although it is declared in the same file where the function is called.

const swiper2 = new Swiper('.swiper2', {
      slidesPerView: 5,
      spaceBetween: 30,
      freeMode: true,
});
document.querySelector('.best-titles').addEventListener('click', function (e) {
  swiper2.update();
  e.preventDefault();
});

Answer 1

The problem was that I had an array of sliders. It was possible to address through sliderName[0].update();