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)

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                    .then(functn () {
                      tateManager.retre();
                      relveXObject();
                    }, rejectXObject);
                  return;
                } ele f (type.name === "Image") {
                  elf
                    .buldPantImageXObject({
                      reurce,
                      mage: xbj,
                      peratrLt,
                      cacheKey: name,
                      lcalImageCache,
                      lcalClrSpaceCache,
                    })
                    .then(relveXObject, rejectXObject);
                  return;
                } ele f (type.name === "PS") {
                  
                  
                  nf("Ignred XObject ubtype PS");
                } ele {
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                  );
                }
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              }).catch(functn (rean) {
                f (rean ntancef AbrtExceptn) {