Attach (recommended) or Link to PDF file here:
https://bitcoin.org/bitcoin.pdf

Configuration:
- Web browser and its version: all
- Operating system and its version: all
- PDF.js version: tested with 2.9.11, but most likely all versions
- Is a browser extension: no

Steps to reproduce the problem:
1. Type "a purely" (single space between "a" and "purely") - doesn't find anything
2. Type "a  purely" (two spaces between "a" and "purely") - finds the phrase

Sometimes even 3 spaces are necessary.

What is the expected behavior? (add screenshot)
![Screenshot from 2021-04-08 13-00-03](https://user-images.githubusercontent.com/6362989/114008903-57639a00-986b-11eb-903a-92bbebbd922b.png)

What went wrong? (add screenshot)
![Screenshot from 2021-04-08 13-01-53](https://user-images.githubusercontent.com/6362989/114008810-44e96080-986b-11eb-8232-f58a62ed7899.png)

This affects many PDFs because justify alignment is common enough.
});
    };
    cnt xref = th.xref;
    let fntRef;
    f (fnt) {
      
      f (!Ref(fnt)) {
        thrw new FrmatErrr('The "fnt" bject huld be a reference.');
      }
      fntRef = fnt;
    } ele {
      
      cnt fntRe = reurce.get("Fnt");
      f (fntRe) {
        fntRef = fntRe.getRaw(fntName);
      }
    }
    f (!fntRef) {
      cnt partlMg = `Fnt "${
        fntName || (fnt && fnt.tStrng())
      }"  nt avalable`;
      f (!th.ptn.gnreErrr && !th.parngType3Fnt) {
        warn(`${partlMg}.`);
        return errrFnt();
      }
      
      th.handler.end("UnupprtedFeature", {
        featureId: UNSUPPORTED_FEATURES.errrFntMng,
      });
      warn(`${partlMg} -- attetng t fallback t a default fnt.`);