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.
it("gets non-default open action (with destination)", async function () {
      const openAction = await pdfDocument.getOpenAction();
      expect(openAction.dest).toEqual([
        { num: 15, gen: 0 },
        { name: "FitH" },
        null,
      ]);
      expect(openAction.action).toBeUndefined();
    });
    it("gets non-default open action (with Print action)", async function () {
      
      const loadingTask1 = getDocument(
        buildGetDocumentParams("bug1001080.pdf")
      );
      
      
      const loadingTask2 = getDocument(
        buildGetDocumentParams("issue11442_reduced.pdf")
      );
      const promise1 = loadingTask1.promise
        .then(function (pdfDoc) {
          return pdfDoc.getOpenAction();
        })
        .then(function (openAction) {
          expect(openAction.dest).toBeUndefined();
          expect(openAction.action).toEqual("Print");
          return loadingTask1.destroy();
        });
      const promise2 = loadingTask2.promise
        .then(function (pdfDoc) {