the xxdiff package seems to have gone missing in Raring Ringtail. Does anyone know what the problemis / how to get it back?
xxdiff is available in the default repositories for Ubuntu 16.04 and later.
xxdiff isn't available in the default Ubuntu 13.04 repositories, but there are other packages available in the default Ubuntu repositories that are similar to xxdiff, among them docdiff and dwdiff. docdiff and dwdiff are also available for all currently supported versions of Ubuntu.