How to combine slick slider and magnific popup correctly?

Question

JavaScript

Using slick slider + magnific popup: example .
It is necessary that when you click on a certain button, the desired slide opens, for example, when you click on button 2, slide 2 opens in a row, when you click on 3, slide 3 opens, etc.
When you press the first time, everything works, but the second and subsequent times it does not work.

Answer 1

$('.popup-link').magnificPopup({
  midClick: true,
  type: 'inline',
  callbacks: {
    open() {
      const $slider = $('.slider');

      if (!$slider.hasClass('slick-initialized')) {
        $slider.slick({
          infinite: true,
          slidesToShow: 1,
          dots: true,
        });
      }

      $slider.slick('slickGoTo', +$(this).attr('index'));
    },
  },
});