README for librsvg
NOTES
Version 2.39.0 is the last one with support for GTK+2:
http://ftp.acc.umu.se/pub/GNOME/sources/librsvg/2.40/librsvg-2.40.0.news
POST-INSTALL
For this application to work properly with SVG-based themes, you must
update your gdk-pixbuf.loaders:
# gdk-pixbuf-query-loaders > /usr/etc/gtk-2.0/gdk-pixbuf.loaders
To do that also you can execute the post-install script.