When I do a search in some LaTeX documents in the Mac OS X app Preview, I get some strange characters in the search results. These seem to be characters inserted by macros, e.g. by biblatex. The respective letters, e.g. page numbers in a citation, cannot be found via the search either.
I suspect it could be a combination of XeLaTeX and biblatex documents. You can reproduce the phenomenon in the documentation to biblatex-dw, which also uses XeLaTeX and biblatex. However, neither in the original biblatex documentation (pdflatex) or the XeLaTeX documentation (without biblatex) does it happen.
In Acrobat Reader this problem does not occur because the results are not listed.
Does anyone know how to avoid this? The bigger problem is of course that some words cannot be searched.
Edit by moewe: The following MWE reproduces the problem when run with XeLaTeX
\documentclass{article}
\usepackage[osf]{libertine}
\begin{document}
lorem 2015
\end{document}
Edit: @moewe: Thanks for the hints.
Strange thing happened: as I was searching the site for questions related to xelatex/oldstyle numbers, I was convinced that my question was a duplicate of Small-caps, old-style numbers, and some ligatures produce odd symbols in PDF copy text? and I would have to change to LuaLaTeX. But now the problem does not seem to exist anymore for me in newly compiled documents! Neither the suggested MWE nor the example in the linked question nor my own document has this problem. In a two-year old version of the document the problem is there, but not in a newly compiled one (TeX Live 2012 vs 2014). Have there been any changes in the last year regarding the xetex font problem that might have solved it?
biblatex-dwdocumentation in "Author: Title, in: Book, pp. 100-150.": the string "Author: Title, in: Book, pp." is fine, while "100-150" cannot be copied. The problem could be reproduced with SumatraPDF and Adobe Reader (on Windows 7). Maybe it has to do with old style numbering. You will find that no number at all can be found or copied - the all become weird unicode characters. Could you come up with a minimal document that shows this error? I suspect it is notbiblatex's fault.biblatex, just with old style figures.3.14159265-2.6-0.99991) I get Unicode U+E11A for "2" (and so on) when copying the characters (ins SumatraPDF as well as AdobeReader).