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

let charCodes = null;
      for (const charCode in charCodeToGlyphId) {
        if (glyphId === charCodeToGlyphId[charCode]) {
          if (!charCodes) {
            charCodes = [];
          }
          charCodes.push(charCode | 0);
        }
      }
      return charCodes;
    }
    function createCharCode(charCodeToGlyphId, glyphId) {
      for (const charCode in charCodeToGlyphId) {
        if (glyphId === charCodeToGlyphId[charCode]) {
          return charCode | 0;
        }
      }
      newMapping.charCodeToGlyphId[newMapping.nextAvailableFontCharCode] =
        glyphId;
      return newMapping.nextAvailableFontCharCode++;
    }
    const seacs = font.seacs;
    if (newMapping && SEAC_ANALYSIS_ENABLED && seacs && seacs.length) {
      const matrix = properties.fontMatrix || FONT_IDENTITY_MATRIX;
      const charset = font.getCharset();
      const seacMap = Object.create(null);
      for (let glyphId in seacs) {
        glyphId |= 0;
        const seac = seacs[glyphId];
        const baseGlyphName = StandardEncoding[seac[2]];