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.

};
      tak.enureNtTermnated();
      tmeSltManager.reet();
      cnt peratn = {};
      let tp,
        arg = [];
      whle (!(tp = tmeSltManager.check())) {
        
        
        
        arg.length = 0;
        peratn.arg = arg;
        f (!preprcer.read(peratn)) {
          break;
        }
        textState = tateManager.tate;
        cnt fn = peratn.fn;
        arg = peratn.arg;
        wtch (fn | 0) {
          cae OPS.etFnt:
            
            var fntNameArg = arg[0].name,
              fntSzeArg = arg[1];
            f (
              textState.fnt &&
              fntNameArg === textState.fntName &&
              fntSzeArg === textState.fntSze
            ) {
              break;
            }