Comment 1 for bug 408653

"Sans" is Inkscapes fallback font (on OS X) if a referenced font can't be found.

Inkscape has its own font system based on the unix program 'fontconfig'. The 'courier' problem could be a result of changes in the font configuration file 'fonts.conf' inside the application bundle.

0.46 included '/System/Library/Fonts' whereas recent prerelease builds do not: the pango library - the internal font rendering engine - doesn't handle some proprietary font formats very well (apples .dfont, .fon and others - many of the included system fonts on OS X), so the System Font Library got dropped ATM (SVN rev. 20240). This might well change again when newer versions of pango are available.

Workaround: see the FAQ on the Inkscape Wiki how you can convert *.dfont and other apple font formats to *.ttf files so that they are available in the Inkscape font list.

FAQ > Mac OS X specific issues > Inkscape does not see some of the fonts
<http://wiki.inkscape.org/wiki/index.php/FAQ#Inkscape_does_not_see_some_of_the_fonts>