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.
"ksc-5601",
          "none",
          "shift-jis",
          "ucs-2",
          "utf-16",
        ].includes(k) || k.match(/iso-8859-[0-9]{2}/),
    });
    this.use = attributes.use || "";
    this.usehref = attributes.usehref || "";
    this.xdpContent = attributes.xdpContent || "";
    this.encrypt = null;
    this.encryptData = new XFAObjectArray();
    this.signData = new XFAObjectArray();
  }
}
class Template extends XFAObject {
  constructor(attributes) {
    super(TEMPLATE_NS_ID, "template",  true);
    this.baseProfile = getStringOption(attributes.baseProfile, [
      "full",
      "interactiveForms",
    ]);
    this.extras = null;
    
    
    
    
    this.subform = new XFAObjectArray();
  }
  [$finalize]() {