how to force download javascript

JavaScript
function downloadFile(data, fileName, type="text/plain") {
  // Create an invisible A element
  const a = document.createElement("a");
  a.style.display = "none";
  document.body.appendChild(a);

  // Set the HREF to a Blob representation of the data to be downloaded
  a.href = window.URL.createObjectURL(
    new Blob([data], { type })
  );

  // Use download attribute to set set desired file name
  a.setAttribute("download", fileName);

  // Trigger the download by simulating click
  a.click();

  // Cleanup
  window.URL.revokeObjectURL(a.href);
  document.body.removeChild(a);
}
Source

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