How to handle dynamically created elements? about in-view HOT 4 CLOSED

var observer = new MutationObserver(function(mutations) {
      mutations.forEach(function(mutation) {
        if (!mutation.addedNodes) {
          return;
        }

        if (document.querySelector(selector)) {
          inView(selector).on('enter', (e) => onEnter(e));
          observer.disconnect();
          return;
        }
      });
    });

    observer.observe(document.body, {
      childList: true,
      subtree: true,
      attributes: false,
      characterData: false
    });

window.document.dispatchEvent(new Event("DOMContentLoaded", {
  bubbles: true,
  cancelable: true
}));