I am making a website that downloads mp3s from YouTube. I have made a progress bar using event source. I create these listeners to make progress bars? How do I terminate one early (if a user makes a new request).

   mp4EventSource = new EventSource(`/${id}/mp4Event`);

                      function getVidProgress () {
                                  mp4EventSource.addEventListener(`progress${id}`, updateMp4Data);
                                  return () => mp4EventSource.close();
                                };