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)

if (this.data.quadPoints === null) {
      return false;
    }
    if (this.flags === 0) {
      return false;
    }
    return this._isPrintable(this.flags);
  }
  /**
   * Set the contents.
   *
   * @public
   * @memberof Annotation
   * @param {string} contents - Text to display for the annotation or, if the
   *                            type of annotation does not display text, a
   *                            description of the annotation's contents
   */
  setContents(contents) {
    this.contents = stringToPDFString(contents || "");
  }
  /**
   * Set the modification date.
   *
   * @public
   * @memberof Annotation
   * @param {string} modificationDate - PDF date string that indicates when the
   *                                    annotation was last modified
   */
  setModificationDate(modificationDate) {