Mutter is a small window manager, using GTK+ and Clutter to do everything. . Mutter is the clutter-based evolution of Metacity, which, as the author says, is a "Boring window manager for the adult in you. Many window managers are like Marshmallow Froot Loops; Metacity is like Cheerios." . This package contains the GObject introspection data which may be used to generate dynamic bindings.