
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)


charCode >= 0xf000 &&
              charCode <= 0xf0ff
            ) {
              charCode &= 0xff;
            }
            charCodeToGlyphId[charCode] = cmapMappings[i].glyphId;
          }
        }
        
        if (properties.glyphNames && baseEncoding.length) {
          for (let i = 0; i < 256; ++i) {
            if (charCodeToGlyphId[i] === undefined && baseEncoding[i]) {
              glyphName = baseEncoding[i];
              const glyphId = properties.glyphNames.indexOf(glyphName);
              if (glyphId > 0 && hasGlyph(glyphId)) {
                charCodeToGlyphId[i] = glyphId;
              }
            }
          }
        }
      }
      if (charCodeToGlyphId.length === 0) {
        
        charCodeToGlyphId[0] = 0;
      }
      
      
      
      
      let glyphZeroId = numGlyphsOut - 1;