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)

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) {