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.
if (this.pinned) {
      this._hide(true);
    } else {
      this._show(true);
    }
  }
  /**
   * Show the popup.
   *
   * @private
   * @param {boolean} pin
   * @memberof PopupElement
   */
  _show(pin = false) {