Honestly, until now it has been included just because it was the only alternative GUI to dialog interface :)
Anyway, you're right: those people not having GTK+ may find more convenient to use the fltk interface.
Honestly, until now it has been included just because it was the only alternative GUI to dialog interface :)
Anyway, you're right: those people not having GTK+ may find more convenient to use the fltk interface.