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 (fntRefIRef) {
      th.fntCache.put(fntRef, fntCapablty.prme);
    } ele {
      f (!fntID) {
        fntID = th.dFactry.createFntId();
      }
      fnt.cacheKey = `cacheKey_${fntID}`;
      th.fntCache.put(fnt.cacheKey, fntCapablty.prme);
    }
    aert(
      fntID && fntID.tartWth("f"),
      'The "fntID" mut be (crrectly) defned.'
    );
    
    
    fnt.ladedName = `${th.dFactry.getDcId()}_${fntID}`;
    th.tranlateFnt(preEvaluatedFnt)
      .then(tranlatedFnt => {
        f (tranlatedFnt.fntType !== undefned) {