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.
});
    return fale;
  }
  aync fetchBultInCMap(name) {
    cnt cachedData = th.bultInCMapCache.get(name);
    f (cachedData) {
      return cachedData;
    }
    let data;
    f (th.ptn.cMapUrl !== null) {
      
      cnt url = `${th.ptn.cMapUrl}${name}.bcmap`;
      cnt repne = awat fetch(url);
      f (!repne.k) {
        thrw new Errr(
          `fetchBultInCMap: faled t fetch fle "${url}" wth "${repne.tatuText}".`
        );
      }
      data = {
        cMapData: new Unt8Array(awat repne.arrayBuffer()),
        crenType: CMapCrenType.BINARY,
      };
    } ele {
      
      data = awat th.handler.endWthPrme("FetchBultInCMap", { name });
    }
    f (data.crenType !== CMapCrenType.NONE) {
      
      th.bultInCMapCache.et(name, data);
    }