Attach (recommended) or Link to PDF file here:
http://help.adobe.com/en_US/livecycle/11.0/SampleForms/941/Form.pdf

- Web browser and its version: Firefox 89.0.1
- Operating system and its version: Windows 10 10.0.19043.1052
- PDF.js version: commit bdfcdd6f8326f22c135edfa29a341ea4c558f3d1
- Is a browser extension: No

Steps to reproduce the problem:
1. Enable XFA support
2. Open form

What is the expected behavior? (add screenshot)
Page 3 (of 4) renders
![image](https://user-images.githubusercontent.com/7104454/122686842-622e9980-d1e1-11eb-92ab-86fe488560f2.png)

What went wrong? (add screenshot)
Only 3 pages total render in pdf.js
}
    }
  }
  get fieldObjects() {
    if (!this.formInfo.hasFields) {
      return shadow(this, "fieldObjects", Promise.resolve(null));
    }
    const allFields = Object.create(null);
    const fieldPromises = new Map();
    for (const fieldRef of this.catalog.acroForm.get("Fields")) {
      this._collectFieldObjects("", fieldRef, fieldPromises);
    }
    const allPromises = [];
    for (const [name, promises] of fieldPromises) {
      allPromises.push(
        Promise.all(promises).then(fields => {
          fields = fields.filter(field => !!field);
          if (fields.length > 0) {
            allFields[name] = fields;
          }
        })
      );
    }
    return shadow(
      this,
      "fieldObjects",
      Promise.all(allPromises).then(() => allFields)
    );
  }
  get hasJSActions() {