Attach (recommended) or Link to PDF file here:
[test.pdf](https://github.com/mozilla/pdf.js/files/6715502/test.pdf)

Configuration:
- Web browser and its version: Google Chrome Version 91.0.4472.114 
- Operating system and its version: Windows 10 Enterprise
- PDF.js version: 
- Is a browser extension: yes

Steps to reproduce the problem:
1. download file
2. open file



What is the expected behavior? (add screenshot)
show symbol
![image](https://user-images.githubusercontent.com/50500976/123409847-55ca8800-d5b7-11eb-9e5b-c7f3b33c00e1.png)

What went wrong? (add screenshot)
Does not show symbol
![image](https://user-images.githubusercontent.com/50500976/123409707-274cad00-d5b7-11eb-9a64-b11dcf3cdc3f.png)
Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension): Latest Version Chrome extension

strBuf.length = stringLength;
            for (i = 0; i < stringLength; ++i) {
              strBuf[i] = String.fromCharCode(font.getByte());
            }
            customNames.push(strBuf.join(""));
          }
          glyphNames = [];
          for (i = 0; i < numGlyphs; ++i) {
            const j = glyphNameIndexes[i];
            if (j < 258) {
              glyphNames.push(MacStandardGlyphOrdering[j]);
              continue;
            }
            glyphNames.push(customNames[j - 258]);
          }
          break;
        case 0x00030000:
          break;
        default:
          warn("Unknown/unsupported post table version " + version);
          valid = false;
          if (propertiesObj.defaultEncoding) {
            glyphNames = propertiesObj.defaultEncoding;
          }
          break;
      }
      propertiesObj.glyphNames = glyphNames;
      return valid;
    }
    function readNameTable(nameTable) {