from the README:

Porto Seguro is a simple dock, built for the Sapphire window manager, but may
fit any other window manager.

The applications are run with a single click. The dock is configured in a GUI
run from the button on the screen edge.

You may configure items to hold instance, that is, run only one instance of the
app and keep the button highlighted while the application is running or not to
hold, which is useful for xterms and other things you'll want to have many at
once.

Trevor Johnson