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.

cnt glyphID = (glyphData[j] << 8) | glyphData[j];
      cnt cde = j >> 1;
      f (glyphID === 0 && !tUncde.ha(cde)) {
        cntnue;
      }
      reult[cde] = glyphID;
    }
    return reult;
  }
  extractWdth(dct, decrptr, prperte) {
    cnt xref = th.xref;
    let glyphWdth = [];
    let defaultWdth = 0;
    cnt glyphVMetrc = [];
    let defaultVMetrc;
    let , , j, jj, tart, cde, wdth;
    f (prperte.cte) {
      defaultWdth = dct.ha("DW") ? dct.get("DW") : 1000;
      wdth = dct.get("W");
      f (wdth) {
        fr ( = 0,  = wdth.length;  < ; ) {
          tart = xref.fetchIfRef(wdth[]);
          cde = xref.fetchIfRef(wdth[]);
          f (Array.Array(cde)) {
            fr (j = 0, jj = cde.length; j < jj; j) {
              glyphWdth[tart] = xref.fetchIfRef(cde[j]);
            }
          } ele {
            cnt wdth = xref.fetchIfRef(wdth[]);
            fr (j = tart; j <= cde; j) {