Download All Videos in a Page

function download(url) {
  return new Promise((res, rej) => {
    fetch(url)
      .then((res) => res.blob())
      .then((file) => {
        const tempUrl = URL.createObjectURL(file);
        const aTag = document.createElement("a");
        aTag.href = tempUrl;
        aTag.download = url.replace(/^.*[\\\/]/, "");
        document.body.appendChild(aTag);
        aTag.click();
        URL.revokeObjectURL(tempUrl);
        aTag.remove();
        res();
      })
      .catch((err) => {
        rej(err);
      });
  });
}

// Get all the video elements on the page.
const videos = document.querySelectorAll("video");

// Iterate over the video elements and download each video.
videos.forEach((video) => {
  // Get the video URL.
  const videoUrl = video.src;
  download(videoUrl);
});