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("creates pdf doc from non-existent URL", async function () {
      if (!isNodeJS) {
        
        pending("Fails intermittently on Linux in browsers.");
      }
      const loadingTask = getDocument(
        buildGetDocumentParams("non-existent.pdf")
      );
      expect(loadingTask instanceof PDFDocumentLoadingTask).toEqual(true);
      try {
        await loadingTask.promise;
        
        expect(false).toEqual(true);
      } catch (reason) {
        expect(reason instanceof MissingPDFException).toEqual(true);
      }
      await loadingTask.destroy();
    });
    it("creates pdf doc from PDF file protected with user and owner password", async function () {
      const loadingTask = getDocument(buildGetDocumentParams("pr6531_1.pdf"));
      expect(loadingTask instanceof PDFDocumentLoadingTask).toEqual(true);
      const passwordNeededCapability = createPromiseCapability();
      const passwordIncorrectCapability = createPromiseCapability();
      
      
      loadingTask.onPassword = function (updatePassword, reason) {
        if (
          reason === PasswordResponses.NEED_PASSWORD &&
          !passwordNeededCapability.settled