
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)


safeString16(properties.ascent) + 
          string16(properties.italicAngle ? 2 : 0) + 
          "\x00\x11" + 
          "\x00\x00" + 
          "\x00\x00" + 
          "\x00\x00"
      ); 
      
      builder.addTable(
        "hhea",
        "\x00\x01\x00\x00" + 
          safeString16(properties.ascent) + 
          safeString16(properties.descent) + 
          "\x00\x00" + 
          "\xFF\xFF" + 
          "\x00\x00" + 
          "\x00\x00" + 
          "\x00\x00" + 
          safeString16(properties.capHeight) + 
          safeString16(Math.tan(properties.italicAngle) * properties.xHeight) + 
          "\x00\x00" + 
          "\x00\x00" + 
          "\x00\x00" + 
          "\x00\x00" + 
          "\x00\x00" + 
          "\x00\x00" + 
          string16(numGlyphs)
      ); 
      
      builder.addTable(