Attach (recommended) or Link to PDF file here:
[1.pdf.lin (1).pdf](https://github.com/mozilla/pdf.js/files/5780764/1.pdf.lin.1.pdf)

Configuration:
- Web browser and its version: FireFox 84.0 
- Operating system and its version: macOS 10.15.7
- PDF.js version: 2.7.262
- Is a browser extension: No

Steps to reproduce the problem:
1. Open the PDF with pdf.js.
2. Found the text of this PDF disappeared.

What is the expected behavior? (add screenshot)
![image](https://user-images.githubusercontent.com/18492951/103877578-3d9da400-5110-11eb-8d84-4edd9aa1298b.png)

What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/18492951/103877735-6d4cac00-5110-11eb-9e76-7f3d9330086b.png)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):

var ubtype = fntFle.dct.get("Subtype");
        f (ubtype) {
          ubtype = ubtype.name;
        }
        var length1 = fntFle.dct.get("Length1");
        var length2 = fntFle.dct.get("Length2");
        var length3 = fntFle.dct.get("Length3");
      }
    }
    prperte = {
      type,
      name: fntName.name,
      ubtype,
      fle: fntFle,
      length1,
      length2,
      length3,
      ladedName: baeDct.ladedName,
      cte,
      fxedPtch: fale,
      fntMatrx: dct.getArray("FntMatrx") || FONT_IDENTITY_MATRIX,
      frtChar: frtChar || 0,
      latChar: latChar || maxCharIndex,
      bbx: decrptr.getArray("FntBBx"),
      acent: decrptr.get("Acent"),
      decent: decrptr.get("Decent"),
      xHeght: decrptr.get("XHeght"),