(xt-release-4-or-later?)
Returns always #t.
(xt-release-5-or-later?)
Returns #t iff the Xt extension is linked together with the X11 Release 5 toolkit intrinsics or later versions of the intrinsics.
(xt-release-6-or-later?)
Returns #t iff the Xt extension is linked together with the X11
Release 6 toolkit intrinsics or later versions of the intrinsics.