Attach (recommended) or Link to PDF file here:

Configuration:
- Web browser and its version: Version 81.0.4044.138 (Official Build) (32-bit)
- Operating system and its version: Windows 10
- PDF.js version: latest
- Is a browser extension: no

Steps to reproduce the problem:

1. Open https://mozilla.github.io/pdf.js/web/viewer.html
2. Open the provided document
3. ctrl + F  and search for 'costs' .
4. Search for 'costs' - match NOT found.
5. Click the 'Download' and open the file in Adobe Reader, and search for costs - match is found.

What is the expected behavior? (add screenshot)
The word 'costs' to be returned by search

What went wrong? (add screenshot)
No results found

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):  https://mozilla.github.io/pdf.js/web/viewer.html
[2001_IESC_63_5_v6.pdf](https://github.com/mozilla/pdf.js/files/4644486/2001_IESC_63_5_v6.pdf)

"non-existent-named-destination"
      );
      expect(destination).toEqual(null);
    });
    it("gets destinations, from /Names (NameTree) dictionary", async function () {
      const loadingTask = getDocument(buildGetDocumentParams("issue6204.pdf"));
      const pdfDoc = await loadingTask.promise;
      const destinations = await pdfDoc.getDestinations();
      expect(destinations).toEqual({
        "Page.1": [{ num: 1, gen: 0 }, { name: "XYZ" }, 0, 375, null],
        "Page.2": [{ num: 6, gen: 0 }, { name: "XYZ" }, 0, 375, null],
      });
      await loadingTask.destroy();
    });
    it("gets a destination, from /Names (NameTree) dictionary", async function () {
      const loadingTask = getDocument(buildGetDocumentParams("issue6204.pdf"));
      const pdfDoc = await loadingTask.promise;
      const destination = await pdfDoc.getDestination("Page.1");
      expect(destination).toEqual([
        { num: 1, gen: 0 },
        { name: "XYZ" },
        0,
        375,
        null,
      ]);
      await loadingTask.destroy();
    });
    it("gets a non-existent destination, from /Names (NameTree) dictionary", async function () {
      const loadingTask = getDocument(buildGetDocumentParams("issue6204.pdf"));
      const pdfDoc = await loadingTask.promise;