WnDO (formerly Fbdo) is a small suite of complementary tools for adding behavioral extensions to Gnome, Xfce, Fluxbox, and other window managers. WnDO offers a plugin platform for tweaking the desktop environment. It focuses on modifying behavior, rather than adding desktop widgets. It has minimal dependencies, other than Python. Included modules handle window alignment, simple window tiling, process management, wallpaper management, and custom keyboard shortcuts. Wallpaper management capabilities include per-workspace and randomly-selected wallpaper. It performs its own key grabbing in order to avoid interaction and conflict with the equivalent window manager facility. It requires CmDO.