Attach (recommended) or Link to PDF file here:
https://www.canada.ca/content/dam/ircc/migration/ircc/english/pdf/kits/forms/eimm5669e.pdf
[eimm5669e.pdf](https://github.com/mozilla/pdf.js/files/7225677/eimm5669e.2.pdf)

Configuration:
- Web browser and its version: Firefox nightly
- Operating system and its version: Linux Debian

Steps to reproduce the problem:
1. Look at the bottom of page 2

if (this.exData) {
      if (typeof this.exData[$content] === "string") {
        return this.exData[$content].trim();
      }
      return this.exData[$content][$text]().trim();
    }
    for (const name of Object.getOwnPropertyNames(this)) {
      if (name === "image") {
        continue;
      }
      const obj = this[name];
      if (obj instanceof XFAObject) {
        return (obj[$content] || "").toString().trim();
      }
    }
    return null;
  }
  [$toHTML](availableSpace) {
    for (const name of Object.getOwnPropertyNames(this)) {
      const obj = this[name];
      if (!(obj instanceof XFAObject)) {
        continue;
      }
      return obj[$toHTML](availableSpace);
    }
    return HTMLResult.EMPTY;
  }
}
class Variables extends XFAObject {