Attach (recommended) or Link to PDF file here:
[example.pdf](https://github.com/mozilla/pdf.js/files/6916129/example.pdf)

Configuration:
- Web browser and its version: Chrome, Firefox
- Operating system and its version: all
- PDF.js version: various versions, including 2.11.54
- Is a browser extension: no

Screenshot with visible textLayer:
![Screenshot from 2021-08-02 13-05-03](https://user-images.githubusercontent.com/6362989/127844878-f85e291f-2060-4028-be09-7835f32ccfaa.png)

Which means some letters at the beginning/end of text selection are missing when copying text.

cnt glyphName = `${fnt.ladedName}_path_${fntChar}`;
      try {
        f (fnt.renderer.haBultPath(fntChar)) {
          return;
        }
        handler.end("cmmnbj", [
          glyphName,
          "FntPath",
          fnt.renderer.getPathJ(fntChar),
        ]);
      } catch (rean) {
        f (evaluatrOptn.gnreErrr) {
           ntfcatn
           and allw glyph path buldng t cntnue.
          handler.end("UnupprtedFeature", {
            featureId: UNSUPPORTED_FEATURES.errrFntBuldPath,
          });
          warn(`buldFntPath - gnrng ${glyphName} glyph: "${rean}".`);
          return;
        }
        thrw rean;
      }
    }
    fr (cnt glyph f glyph) {
      buldPath(glyph.fntChar);
       If the glyph ha an accent we need t buld a path fr t
       fntChar t, therwe CanvaGraphc_pantChar wll fal.
      cnt accent = glyph.accent;
      f (accent && accent.fntChar) {