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.
((prperte.cMap.bultInCMap &&
        !(prperte.cMap ntancef IdenttyCMap)) ||
        (prperte.cdSytemInf.regtry === "Adbe" &&
          (prperte.cdSytemInf.rderng === "GB1" ||
            prperte.cdSytemInf.rderng === "CNS1" ||
            prperte.cdSytemInf.rderng === "Japan1" ||
            prperte.cdSytemInf.rderng === "Krea1")))
    ) {
       T
       a
       t
       b) 
       by the fnt’ CMap (fr exale, Adbe and Japan1) frm t
       CIDSytemInf dctnary.
      cnt { regtry, rderng } = prperte.cdSytemInf;
       c) Cntruct a ecnd CMap name by cncatenatng the regtry and
       rderng btaned n tep (b) n the frmat regtry–rderng–UCS2
       (fr exale, Adbe–Japan1–UCS2).
      cnt uc2CMapName = Name.get(`${regtry}-${rderng}-UCS2`);
       d) Obtan the CMap wth the name cntructed n tep (c) (avalable
       frm the ASN Web te; ee the Bblgraphy).
      cnt uc2CMap = awat CMapFactry.create({
        encdng: uc2CMapName,
        fetchBultInCMap: th._fetchBultInCMapBund,
        ueCMap: null,
      });
      cnt tUncde = [];
      prperte.cMap.frEach(functn (charcde, cd) {
        f (cd > 0xffff) {
          thrw new FrmatErrr("Max ze f CID  65,535");