Attach (recommended) or Link to PDF file here:
[docOficialPDF.php.pdf](https://github.com/mozilla/pdf.js/files/7159923/docOficialPDF.php.pdf)

Configuration:
- Web browser and its version: Firefox nightly
- Operating system and its version: linux debian
- PDF.js version: built-in viewer
- Is a browser extension: no

Steps to reproduce the problem:
1. Open the pdf page 2
2. Checkbox "Alta" in section 2 must be checked

It works fine with evince.
constructor(params) {
    super(params);
    this.checkedAppearance = null;
    this.uncheckedAppearance = null;
    this.data.checkBox =
      !this.hasFieldFlag(AnnotationFieldFlag.RADIO) &&
      !this.hasFieldFlag(AnnotationFieldFlag.PUSHBUTTON);
    this.data.radioButton =
      this.hasFieldFlag(AnnotationFieldFlag.RADIO) &&
      !this.hasFieldFlag(AnnotationFieldFlag.PUSHBUTTON);
    this.data.pushButton = this.hasFieldFlag(AnnotationFieldFlag.PUSHBUTTON);
    this.data.isTooltipOnly = false;
    if (this.data.checkBox) {
      this._processCheckBox(params);
    } else if (this.data.radioButton) {
      this._processRadioButton(params);
    } else if (this.data.pushButton) {
      this._processPushButton(params);
    } else {
      warn("Invalid field flags for button widget annotation");
    }
  }
  getOperatorList(evaluator, task, renderForms, annotationStorage) {