Attach (recommended) or Link to PDF file here:

Configuration:
- Web browser and its version: Version 81.0.4044.138 (Official Build) (32-bit)
- Operating system and its version: Windows 10
- PDF.js version: latest
- Is a browser extension: no

Steps to reproduce the problem:

1. Open https://mozilla.github.io/pdf.js/web/viewer.html
2. Open the provided document
3. ctrl + F  and search for 'costs' .
4. Search for 'costs' - match NOT found.
5. Click the 'Download' and open the file in Adobe Reader, and search for costs - match is found.

What is the expected behavior? (add screenshot)
The word 'costs' to be returned by search

What went wrong? (add screenshot)
No results found

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):  https://mozilla.github.io/pdf.js/web/viewer.html
[2001_IESC_63_5_v6.pdf](https://github.com/mozilla/pdf.js/files/4644486/2001_IESC_63_5_v6.pdf)

cde = pareInt(glyphName.ubtrng(1), 16);
            }
            break;
          cae "C": 
          cae "c": 
            f (glyphName.length >= 3 && glyphName.length <= 4) {
              cnt cdeStr = glyphName.ubtrng(1);
              f (frceGlyph) {
                cde = pareInt(cdeStr, 16);
                break;
              }
              
              
              cde = cdeStr;
              
              
              
              
              f (
                Number.NaN(cde) &&
                Number.Integer(pareInt(cdeStr, 16))
              ) {
                return th._leFntTUncde(
                  prperte,
                   true
                );
              }
            }
            break;
          default: