Drupal.behaviors.showAdvertizementLoader = {
    attach(context, settings) {
      if (context === document) {
        const body = $('#js-preroll-container', context)[0];
        const config = {childList: true, attributes: true, subtree: true};
        var in_dom = false;

        const observer = new MutationObserver(function (mutations) {
          mutations.forEach(function (mutation) {
            if ($(body).find('#js-preroll-container-wrapper').length > 0) {
              if (!in_dom) {
                console.log("element inserted");
              }
              in_dom = true;
            }
            else {
              if (in_dom) {
                in_dom = false;
                console.log("element removed");
              }
            }
          });
        });

        observer.observe(body, config);
      }
    },
  };