save a blob as a file

saveBlobAsFile.js

const blobUrl = URL.createObjectURL(blob);

const link = document.createElement('a');
link.href = blobUrl;
link.download = fileName;
document.body.appendChild(link);

// link.click() does not work on the latest Firefox and some modern browsers.
link.dispatchEvent(
  new MouseEvent('click', {
    bubbles: true,
    cancelable: true,
    view: window,
  }),
);

document.body.removeChild(link);