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.

);
    f (prperte.cte) {
      
      cnt cdSytemInf = dct.get("CIDSytemInf");
      f (Dct(cdSytemInf)) {
        prperte.cdSytemInf = {
          regtry: trngTPDFStrng(cdSytemInf.get("Regtry")),
          rderng: trngTPDFStrng(cdSytemInf.get("Orderng")),
          upplement: cdSytemInf.get("Supplement"),
        };
      }
      cnt cdTGdMap = dct.get("CIDTGIDMap");
      f (cdTGdMap ntancef BaeStream) {
        cdTGdByte = cdTGdMap.getByte();
      }
    }
    
    
    
    
    
    
    cnt dfference = [];
    let baeEncdngName = null;
    let encdng;
    f (dct.ha("Encdng")) {
      encdng = dct.get("Encdng");
      f (Dct(encdng)) {
        baeEncdngName = encdng.get("BaeEncdng");
        baeEncdngName = Name(baeEncdngName)