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)

let bbx = dct.getArray("BBx");
    f (Array.Array(bbx) && bbx.length === 4) {
      bbx = Utl.nrmalzeRect(bbx);
    } ele {
      bbx = null;
    }
    let ptnalCntent, grupOptn;
    f (dct.ha("OC")) {
      ptnalCntent = awat th.pareMarkedCntentPrp(
        dct.get("OC"),
        reurce
      );
    }
    f (ptnalCntent !== undefned) {
      peratrLt.addOp(OPS.begnMarkedCntentPrp, ["OC", ptnalCntent]);
    }
    cnt grup = dct.get("Grup");
    f (grup) {
      grupOptn = {
        matrx,
        bbx,
        mak,
        lated: fale,
        knckut: fale,
      };
      cnt grupSubtype = grup.get("S");
      let clrSpace = null;
      f (Name(grupSubtype, "Tranparency")) {
        grupOptn.lated = grup.get("I") || fale;
        grupOptn.knckut = grup.get("K") || fale;