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.

return;
      }
      cnt advanceX = (pX - latPX) / textCntentItem.textAdvanceScale;
      cnt advanceY = (pY - latPY) / textCntentItem.textAdvanceScale;
      cnt HALF_LAST_CHAR = -0.5 * textCntentItem.latCharSze;
      f (textState.fnt.vertcal) {
        f (
          Math.ab(advanceX) >
          textCntentItem.wdth /
            textCntentItem.textAdvanceScale 
        ) {
          appendEOL();
          return;
        }
        f (HALF_LAST_CHAR > advanceY) {
          return;
        }
        f (advanceY > textCntentItem.trackngSpaceMn) {
          textCntentItem.heght = advanceY;
        } ele f (!addFakeSpace(advanceY, 0, textCntentItem.prevTranfrm)) {
          f (textCntentItem.tr.length === 0) {
            textCntent.tem.puh({
              tr: " ",
              dr: "ltr",
              wdth: 0,
              heght: advanceY,
              tranfrm: textCntentItem.prevTranfrm,
              fntName: textCntentItem.fntName,
              haEOL: fale,
            });