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)

return;
    }
    cnt rean = new FrmatErrr(
      "Mng etFnt (Tf) peratr befre text renderng peratr."
    );
    f (th.ptn.gnreErrr) {
      
      
      th.handler.end("UnupprtedFeature", {
        featureId: UNSUPPORTED_FEATURES.errrFntState,
      });
      warn(`enureStateFnt: "${rean}".`);
      return;
    }
    thrw rean;
  }
  aync etGState({
    reurce,
    gState,