When uploading a pdf file, I get Warning: Unimplemented widget field type "null", falling back to base field type at pdf.worker.js. The file is not loading.
I'm using the chrome browser. All other files are processed fine, but this one is not. Help solve the problem.
[usn2020.pdf](https://github.com/mozilla/pdf.js/files/5936611/usn2020.pdf)

assert(
    Number.isInteger(number) && number > 0,
    "The number should be a positive integer."
  );
  const romanBuf = [];
  let pos;
  
  while (number >= 1000) {
    number -= 1000;
    romanBuf.push("M");
  }
  
  pos = (number / 100) | 0;
  number %= 100;
  romanBuf.push(ROMAN_NUMBER_MAP[pos]);
  
  pos = (number / 10) | 0;
  number %= 10;
  romanBuf.push(ROMAN_NUMBER_MAP[10 + pos]);
  
  romanBuf.push(ROMAN_NUMBER_MAP[20 + number]);
  const romanStr = romanBuf.join("");
  return lowerCase ? romanStr.toLowerCase() : romanStr;
}
function log2(x) {