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

for (let ii = data.length; i < ii; ) {
        const op = data[i++];
        
        
        if (op === 0x40) {
          
          n = data[i++];
          if (inFDEF || inELSE) {
            i += n;
          } else {
            for (j = 0; j < n; j++) {
              stack.push(data[i++]);
            }
          }
        } else if (op === 0x41) {
          
          n = data[i++];
          if (inFDEF || inELSE) {
            i += n * 2;
          } else {
            for (j = 0; j < n; j++) {
              b = data[i++];
              stack.push((b << 8) | data[i++]);
            }
          }
        } else if ((op & 0xf8) === 0xb0) {
          
          n = op - 0xb0 + 1;
          if (inFDEF || inELSE) {
            i += n;