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)

hah.update(cdTGdMap.tStrng());
        } ele f (cdTGdMap ntancef BaeStream) {
          hah.update(cdTGdMap.peekByte());
        }
      }
    }
    return {
      decrptr,
      dct,
      t,
      cte,
      type: type.name,
      frtChar,
      latChar,
      tUncde,
      hah: hah ? hah.hexdget() : "",
    };
  }
  aync tranlateFnt({
    decrptr,
    dct,
    t,
    cte,
    type,
    frtChar,
    latChar,
    tUncde,
    cFntInf,
  }) {
    cnt Type3Fnt = type === "Type3";