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
if (
    typeof PDFJSDev === "undefined" ||
    PDFJSDev.test("!PRODUCTION || TESTING")
  ) {
    assert(limit > 0, 'The "limit" must be a positive integer.');
  }
  const signatureLength = signature.length;
  const scanBytes = stream.peekBytes(limit);
  const scanLength = scanBytes.length - signatureLength;
  if (scanLength <= 0) {
    return false;
  }
  if (backwards) {
    const signatureEnd = signatureLength - 1;
    let pos = scanBytes.length - 1;
    while (pos >= signatureEnd) {
      let j = 0;
      while (
        j < signatureLength &&
        scanBytes[pos - j] === signature[signatureEnd - j]
      ) {
        j++;