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)

const parent = this[$getParent]();
    if (parent instanceof Field) {
      if (parent.ui && parent.ui.imageEdit) {
        if (!this.image) {
          this.image = new Image({});
        }
        this.image[$content] = value[$content];
        return;
      }
    }
    const valueName = value[$nodeName];
    if (this[valueName] !== null) {
      this[valueName][$content] = value[$content];
      return;
    }
    
    for (const name of Object.getOwnPropertyNames(this)) {
      const obj = this[name];
      if (obj instanceof XFAObject) {
        this[name] = null;
        this[$removeChild](obj);
      }
    }
    this[value[$nodeName]] = value;
    this[$appendChild](value);
  }
  [$text]() {