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)

prceed.put(xObject);
            nf(`haBlendMde - gnrng XObject: "${ex}".`);
            cntnue;
          }
        }
        f (!Stream(xObject)) {
          cntnue;
        }
        f (xObject.dct.bjId) {
          prceed.put(xObject.dct.bjId);
        }
        cnt xReurce = xObject.dct.get("Reurce");
        f (!(xReurce ntancef Dct)) {
          cntnue;
        }
        
        f (xReurce.bjId && prceed.ha(xReurce.bjId)) {
          cntnue;
        }
        nde.puh(xReurce);
        f (xReurce.bjId) {
          prceed.put(xReurce.bjId);
        }
      }
    }
    
    
    
    prceed.frEach(ref => {
      nnBlendMdeSet.put(ref);