Attach (recommended) or Link to PDF file here:
issue13500 (in test corpus)

This regressed when landing #13566. 

What is the expected behavior? (add screenshot)
<img width="664" alt="image" src="https://user-images.githubusercontent.com/942640/122467522-7bc8aa80-cf6f-11eb-9d4d-311eb7c64fb2.png">


What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/942640/122467565-85eaa900-cf6f-11eb-9c10-8a8686ed440c.png)


constructor(attributes) {
    super(TEMPLATE_NS_ID, "subjectDN");
    this.delimiter = attributes.delimiter || ",";
    this.id = attributes.id || "";
    this.name = attributes.name || "";
    this.use = attributes.use || "";
    this.usehref = attributes.usehref || "";
  }
  [$finalize]() {
    this[$content] = new Map(
      this[$content].split(this.delimiter).map(kv => {
        kv = kv.split("=", 2);
        kv[0] = kv[0].trim();
        return kv;
      })
    );
  }
}
class SubjectDNs extends XFAObject {
  constructor(attributes) {
    super(TEMPLATE_NS_ID, "subjectDNs",  true);
    this.id = attributes.id || "";
    this.type = getStringOption(attributes.type, ["optional", "required"]);
    this.use = attributes.use || "";
    this.usehref = attributes.usehref || "";
    this.subjectDN = new XFAObjectArray();
  }
}
class Submit extends XFAObject {