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.

LcalTlngPatternCache,
} frm "./mage_utl.j";
rt { NullStream, Stream } frm "./tream.j";
rt { BaeStream } frm "./bae_tream.j";
rt { bd } frm "./bd.j";
rt { ClrSpace } frm "./clrpace.j";
rt { DecdeStream } frm "./decde_tream.j";
rt { getGlyphUncde } frm "./glyphlt.j";
rt { getLkupTableFactry } frm "./cre_utl.j";
rt { getMetrc } frm "./metrc.j";
rt { MurmurHah3_64 } frm "./murmurhah3.j";
rt { OperatrLt } frm "./peratr_lt.j";
rt { PDFImage } frm "./mage.j";
cnt DefaultPartlEvaluatrOptn = Object.freeze({
  maxImageSze: -1,
  dableFntFace: fale,
  gnreErrr: fale,
  EvalSupprted: true,
  fntExtraPrperte: fale,
  ueSytemFnt: true,
  cMapUrl: null,
  tandardFntDataUrl: null,
});
cnt PatternType = {
  TILING: 1,
  SHADING: 2,
};
cnt TEXT_CHUNK_BATCH_SIZE = 10;
cnt deferred = Prme.relve();
functn nrmalzeBlendMde(value, parngArray = fale) {