Attach (recommended) or Link to PDF file here:
https://www.placementsmondiauxsunlife.com/content/dam/sunlife/regional/canada/documents/slgi/4839-I-F.pdf

Configuration:

- Web browser and its version: 91.0a1 (2021-07-03) (64-bit)
- Operating system and its version: Windows 10

Steps to reproduce the problem:
1. enableXfa = true
2. Open form

What is the expected behavior? (add screenshot)

![image](https://user-images.githubusercontent.com/7104454/124389449-1ede2b80-dcb5-11eb-98ba-01e1f3d6c6f5.png)


What went wrong? (add screenshot)

![image](https://user-images.githubusercontent.com/7104454/124389460-2c93b100-dcb5-11eb-9768-98ddd2c8f1e7.png)

return this.contentType === "text/html";
  }
  [$onChild](child) {
    if (
      this.contentType === "text/html" &&
      child[$namespaceId] === NamespaceIds.xhtml.id
    ) {
      this[$content] = child;
      return true;
    }
    if (this.contentType === "text/xml") {
      this[$content] = child;
      return true;
    }
    return false;
  }
  [$toHTML](availableSpace) {
    if (this.contentType !== "text/html" || !this[$content]) {
      
      return HTMLResult.EMPTY;
    }
    return this[$content][$toHTML](availableSpace);
  }
}
class ExObject extends XFAObject {