Please see the screenshot included in the report "preferences window seems to be missing text/selection fields" - the menu font is barely readable. *t
The referenced screenshot can be found in http://bugs.debian.org/399683 *t
This bug seems to have a root cause for Ubuntu at least in this thread: https://lists.gnu.org/archive/html/ddd/2012-05/msg00001.html In the fonts.c several lucindatypewriter ISO-8859 fonts are requested and those are not present in more recent versions of Ubuntu. The fallback default font is very ugly.