JSesh currently uses a nice library, called Quaqua, to be more Mac-OSX compatible... However, Quaqua development seems to be over (the Java 8 version is still listed as "unstable", so I'm not going to use it).
Jsesh is still functional, but has lost a bit of user-friendliness. For instance, use of the keyboard for selecting list entries is no more functional with Java 8 and Quaqua.
I need to do something about it. It might result in a bit of graphical change... the application will be slightly less mac-like (in particular, it will have bigger buttons).
Sorry for the inconvenience.