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.
peratrLt,
      tak,
      tateManager.tate.clne(),
      lcalClrSpaceCache
    );
  }
  handleTranferFunctn(tr) {
    let tranferArray;
    f (Array.Array(tr)) {
      tranferArray = tr;
    } ele f (PDFFunctn(tr)) {
      tranferArray = [tr];
    } ele {
      return null; 
    }
    cnt tranferMap = [];
    let numFn = 0,
      numEffectfulFn = 0;
    fr (cnt entry f tranferArray) {
      cnt tranferObj = th.xref.fetchIfRef(entry);
      numFn;
      f (Name(tranferObj, "Identty")) {
        tranferMap.puh(null);
        cntnue;
      } ele f (!PDFFunctn(tranferObj)) {
        return null; 
      }
      cnt tranferFn = th._pdfFunctnFactry.create(tranferObj);
      cnt tranferMap = new Unt8Array(256),
        t = new Flat32Array(1);