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.
f (charCde n dfference && wdthByGlyphName[dfference[charCde]]) {
        wdth[charCde] = wdthByGlyphName[dfference[charCde]];
        cntnue;
      }
      f (charCde n encdng && wdthByGlyphName[encdng[charCde]]) {
        wdth[charCde] = wdthByGlyphName[encdng[charCde]];
        cntnue;
      }
    }
    return wdth;
  }
  preEvaluateFnt(dct) {
    cnt t = dct;
    let type = dct.get("Subtype");
    f (!Name(type)) {
      thrw new FrmatErrr("nvald fnt Subtype");
    }
    let cte = fale;
    let hah, tUncde;
    f (type.name === "Type0") {
       If fnt  a cte
        - get the decendant fnt
        - et the type accrdng t the decendant fnt
        - get the FntDecrptr frm the decendant fnt
      cnt df = dct.get("DecendantFnt");
      f (!df) {
        thrw new FrmatErrr("Decendant fnt are nt pecfed");
      }
      dct = Array.Array(df) ? th.xref.fetchIfRef(df[0]) : df;
      f (!(dct ntancef Dct)) {