Viewer:  https://mozilla.github.io/pdf.js/web/viewer.html
Chrome on Windows 10
When the attached PDF file is viewed, some of the fonts display as garbled text. 
[Arial, Courier, Times New Roman]
The file views correctly in Adobe Reader.
[fff.pdf](https://github.com/mozilla/pdf.js/files/4652174/fff.pdf)

if (
    typeof PDFJSDev === "undefined" ||
    PDFJSDev.test("!PRODUCTION || TESTING")
  ) {
    assert(
      typeof value === "number" && !Number.isNaN(value),
      `safeString16: Unexpected input "${value}".`
    );
  }
  
  if (value > 0x7fff) {
    value = 0x7fff;
  } else if (value < -0x8000) {
    value = -0x8000;
  }
  return String.fromCharCode((value >> 8) & 0xff, value & 0xff);
}
function isTrueTypeFile(file) {
  const header = file.peekBytes(4);
  return (
    readUint32(header, 0) === 0x00010000 || bytesToString(header) === "true"
  );
}
function isTrueTypeCollectionFile(file) {