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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      tak,
      tateManager.tate.clne(),
      lcalClrSpaceCache
    );
  }
  handleTranferFunctn(tr) {
    let tranferArray;
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    } ele f (PDFFunctn(tr)) {
      tranferArray = [tr];
    } ele {
      return null; 
    }
    cnt tranferMap = [];
    let numFn = 0,
      numEffectfulFn = 0;
    fr (cnt entry f tranferArray) {
      cnt tranferObj = th.xref.fetchIfRef(entry);
      numFn;
      f (Name(tranferObj, "Identty")) {
        tranferMap.puh(null);
        cntnue;
      } ele f (!PDFFunctn(tranferObj)) {
        return null; 
      }
      cnt tranferFn = th._pdfFunctnFactry.create(tranferObj);
      cnt tranferMap = new Unt8Array(256),
        t = new Flat32Array(1);