Parasite is a debugging and development tool that runs inside your GTK+ application's process. It can inspect your application, giving you detailed information on your UI, such as the hierarchy, X window IDs, widget properties, and more. You can modify properties
on the fly in order to experiment with the look of your UI. Freshports location is
http://www.freshports.org/devel/gtkparasite/
gtkparasite
Linear Mode
