In file https://github.com/mozilla/pdf.js/files/5249872/product1.pdf, the fifth text widget has a default appearance using font F1 and this one is neither in DR nor in AcroForm but in AP::N::Resources.
return (
      this._hasFlag(flags, AnnotationFlag.PRINT) &&
      !this._hasFlag(flags, AnnotationFlag.INVISIBLE)
    );
  }
  isHidden(annotationStorage) {
    const data = annotationStorage && annotationStorage[this.data.id];
    if (data && "hidden" in data) {
      return data.hidden;
    }
    return this._hasFlag(this.flags, AnnotationFlag.HIDDEN);
  }
  /**
   * @type {boolean}
   */
  get viewable() {
    if (this.data.quadPoints === null) {
      return false;
    }
    if (this.flags === 0) {
      return true;
    }
    return this._isViewable(this.flags);
  }
  /**
   * @type {boolean}
   */
  get printable() {