Newer versions of Linux, Solaris, and other Unix flavor desktop environments use GTK3, while still supporting GTK2. Previously, the JDK would default to loading the older GTK2 libraries. However, in this release, it defaults to loading GTK3 libraries. Loading is typically triggered by using the Swing GTK Look And Feel. The old behavior can be restored by using the system property: `-Djdk.gtk.version=2.2`