Attach (recommended) or Link to PDF file here:
https://web.archive.org/web/20091223123331/http://sci2s.ugr.es/keel/pdf/specific/articulo/alp99.pdf
(aka `tests/pdfs/issue1936.pdf`)
 
When I copy/paste the multiplication sign on the first line of the first page, I got a `£`.
And when I do the same in evince I got a `×` (the same in chrome).
The font descriptor is:
```
<< /Ascent 0 /CapHeight 749 /CharSet (/multiply) /Descent 0 /Flags 262212 /FontBBox [ -27 -940 1332 825 ] /FontFile3 59 0 R /FontName /KHPEPJ+CMBSY10 /ItalicAngle -14.035 /StemV 0 /Type /FontDescriptor >>
```
So it should be possible to guess the correct character in using the `CharSet` entry:
https://www.adobe.com/content/dam/acom/en/devnet/pdf/pdfs/PDF32000_2008.pdf#page=291


if (properties.hasIncludedToUnicodeMap) {
    return; 
  }
  if (properties.hasEncoding) {
    return; 
  }
  if (builtInEncoding === properties.defaultEncoding) {
    return; 
  }
  if (properties.toUnicode instanceof IdentityToUnicodeMap) {
    return;
  }
  var toUnicode = [],
    glyphsUnicodeMap = getGlyphsUnicode();
  for (var charCode in builtInEncoding) {
    var glyphName = builtInEncoding[charCode];
    var unicode = getUnicodeForGlyph(glyphName, glyphsUnicodeMap);
    if (unicode !== -1) {
      toUnicode[charCode] = String.fromCharCode(unicode);
    }
  }
  properties.toUnicode.amend(toUnicode);
}
function getFontType(type, subtype) {