firefox-libcairo2
  provides "firefox-cairo-<targettype> = <version>"
  obsoletes "firefox-cairo-<targettype> < <version>"
firefox-libcairo-gobject2
firefox-libcairo-script-interpreter2
firefox-cairo-devel
  requires -firefox-cairo-<targettype>
  requires "firefox-libcairo2-<targettype> = <version>"
  requires "firefox-libcairo-gobject2-<targettype> = <version>"
  requires "firefox-libcairo-script-interpreter2-<targettype> = <version>"