Attach (recommended) or Link to PDF file here:  [test.pdf](https://akmer.aikucun.com/a94a8fe5ccb19ba61c4c0873d391e987982fbbd3_1616477914120_83.pdf)


Configuration:
- Web browser and its version: chrome 87.0.4280.88
- Operating system and its version: windows10
- PDF.js version: 2.6.347
- Is a browser extension:

Steps to reproduce the problem:
1. just open 

What is the expected behavior? (add screenshot)

What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/17724610/112087066-473f8f80-8bc8-11eb-8efb-56139ec42a9c.png)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):

}
    
    var size = 1 << maxLen;
    var codes = new Int32Array(size);
    for (
      var len = 1, code = 0, skip = 2;
      len <= maxLen;
      ++len, code <<= 1, skip <<= 1
    ) {
      for (var val = 0; val < n; ++val) {
        if (lengths[val] === len) {
          
          var code2 = 0;
          var t = code;
          for (i = 0; i < len; ++i) {
            code2 = (code2 << 1) | (t & 1);
            t >>= 1;
          }
          
          for (i = code2; i < size; i += skip) {
            codes[i] = (len << 16) | val;
          }
          ++code;
        }
      }
    }
    return [codes, maxLen];
  };
  FlateStream.prototype.readBlock = function FlateStream_readBlock() {
    var buffer, len;