
Attach (recommended) or Link to PDF file here:
[NAPEN16171380959.pdf](https://github.com/mozilla/pdf.js/files/6143802/NAPEN16171380959.pdf)

Configuration:
- Web browser and its version: Firefox 88 Nightly
- Operating system and its version: Windows 10
- PDF.js version:
- Is a browser extension: No

What went wrong? (add screenshot)
![](https://user-media-prod-cdn.itsre-sumo.mozilla.net/uploads/images/2021-03-15-10-58-27-ce2796.png)


var tag = bytesToString(file.getBytes(4));
        var checksum = file.getInt32() >>> 0;
        var offset = file.getInt32() >>> 0;
        var length = file.getInt32() >>> 0;
        
        var previousPosition = file.pos;
        file.pos = file.start ? file.start : 0;
        file.skip(offset);
        var data = file.getBytes(length);
        file.pos = previousPosition;
        if (tag === "head") {
          
          data[8] = data[9] = data[10] = data[11] = 0;
          data[17] |= 0x20; 
        }
        return {
          tag,
          checksum,
          length,
          offset,
          data,
        };
      }
      function readOpenTypeHeader(ttf) {