To switch the default backend in GNUstep to the corresponding FLAVOR,
enter one of these lines:

* cairo:
  defaults write NSGlobalDomain GSBackend libgnustep-cairo-016

* libart:
  defaults write NSGlobalDomain GSBackend libgnustep-art-016

* xlib:
  defaults write NSGlobalDomain GSBackend libgnustep-back-016
