PDF files:
[1.pdf](https://github.com/mozilla/pdf.js/files/2955999/1.pdf)
[2.pdf](https://github.com/mozilla/pdf.js/files/2956000/2.pdf)
[3.pdf](https://github.com/mozilla/pdf.js/files/2956002/3.pdf)

Configuration:
- Web browser and its version: Chrome, Firefox
- Operating system and its version: Ubuntu, macOS
- PDF.js version: 2.2.42, but the same was with 2.1.x, and with https://mozilla.github.io/pdf.js/web/viewer.html
- Is a browser extension: no

Steps to reproduce the problem:
1. Select text
2. Copy text

What went wrong?

Getting this:
`OpenSansisahumanistsansseriftypefacedesignedbySteveMatteson.OpenSanswasdesignedwithanuprightstress,openformsandaneu-tral,yetfriendlyappearance.Itwasoptimizedforprint,web,andmobileinterfaces,andhasexcellentlegibilitycharacteristicsinitsletterforms(seefigureonthefollowingpage).ThisfontisavailablefromtheGoogleFontDirectory[]asTrueTypefileslicensedundertheApacheLicenseversion..`

Instead of this:
`Open Sans is a humanist sans serif typeface designed by Steve Matteson.
Open Sans was designed with an upright stress, open forms and a neutral,
yet friendly appearance. It was optimized for print, web, and mobile
interfaces, and has excellent legibility characteristics in its letterforms (see
figure 1 on the following page). This font is available from the Google Font
Directory [1] as TrueType files licensed under the Apache License version 2.0.`

This is quite significant problem, because I would say 1/20 of scientific papers encounter this problem.

expect(info.PDFFormatVersion).toEqual("1.7");
      expect(info.IsLinearized).toEqual(false);
      expect(info.IsAcroFormPresent).toEqual(false);
      expect(info.IsXFAPresent).toEqual(false);
      expect(info.IsCollectionPresent).toEqual(false);
      expect(info.IsSignaturesPresent).toEqual(false);
      expect(metadata instanceof Metadata).toEqual(true);
      expect(metadata.get("dc:title")).toEqual("Basic API Test");
      expect(contentDispositionFilename).toEqual(null);
      expect(contentLength).toEqual(basicApiFileLength);
    });
    it("gets metadata, with custom info dict entries", async function () {
      const loadingTask = getDocument(
        buildGetDocumentParams("tracemonkey.pdf")
      );
      const pdfDoc = await loadingTask.promise;
      const { info, metadata, contentDispositionFilename, contentLength } =
        await pdfDoc.getMetadata();
      expect(info.Creator).toEqual("TeX");
      expect(info.Producer).toEqual("pdfeTeX-1.21a");
      expect(info.CreationDate).toEqual("D:20090401163925-07'00'");
      
      const custom = info.Custom;
      expect(typeof custom === "object" && custom !== null).toEqual(true);
      expect(custom["PTEX.Fullbanner"]).toEqual(
        "This is pdfeTeX, " +
          "Version 3.141592-1.21a-2.2 (Web2C 7.5.4) kpathsea version 3.5.6"
      );