Attach (recommended) or Link to PDF file here:
PDF from #4106, https://mail.gnome.org/archives/evince-list/2013-November/pdfNC0hkVW67a.pdf.

Steps to reproduce the problem:
1. Open the PDF

What is the expected behavior?
![immagine](https://user-images.githubusercontent.com/1616846/121865567-67ca4200-ccfe-11eb-8673-1d6e863fc8d5.png)

What went wrong?
The PDF doesn't load, `TypeError: can't access property Symbol(), match is null` error is logged in the console.
return new SubformSet(attrs);
  }
  static subjectDN(attrs) {
    return new SubjectDN(attrs);
  }
  static subjectDNs(attrs) {
    return new SubjectDNs(attrs);
  }
  static submit(attrs) {
    return new Submit(attrs);
  }
  static template(attrs) {
    return new Template(attrs);
  }
  static text(attrs) {
    return new Text(attrs);
  }
  static textEdit(attrs) {
    return new TextEdit(attrs);
  }
  static time(attrs) {
    return new Time(attrs);
  }
  static timeStamp(attrs) {
    return new TimeStamp(attrs);
  }
  static toolTip(attrs) {
    return new ToolTip(attrs);
  }
  static traversal(attrs) {