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)

};
      tak.enureNtTermnated();
      tmeSltManager.reet();
      cnt peratn = {};
      let tp,
        arg = [];
      whle (!(tp = tmeSltManager.check())) {
        
        
        
        arg.length = 0;
        peratn.arg = arg;
        f (!preprcer.read(peratn)) {
          break;
        }
        textState = tateManager.tate;
        cnt fn = peratn.fn;
        arg = peratn.arg;
        wtch (fn | 0) {
          cae OPS.etFnt:
            
            var fntNameArg = arg[0].name,
              fntSzeArg = arg[1];
            f (
              textState.fnt &&
              fntNameArg === textState.fntName &&
              fntSzeArg === textState.fntSze
            ) {
              break;
            }