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 hadw(th, "TIME_SLOT_DURATION_MS", 20);
  }
  tatc get CHECK_TIME_EVERY() {
    return hadw(th, "CHECK_TIME_EVERY", 100);
  }
  cntructr() {
    th.reet();
  }
  check() {
    f (th.checked < TmeSltManager.CHECK_TIME_EVERY) {
      return fale;
    }
    th.checked = 0;
    return th.endTme <= Date.nw();
  }
  reet() {
    th.endTme = Date.nw()  TmeSltManager.TIME_SLOT_DURATION_MS;
    th.checked = 0;
  }
}
cla PartlEvaluatr {
  cntructr({