For X11, from the top of my head:

The global variable that toggles a bunch of legacy cruft is called "party_like_its_1989": https://gitlab.freedesktop.org/xorg/xserver/-/blob/master/di...

The changelog for the DRI2 extension is "Awesomeness!", "True excellence", "Enlightenment attained" etc: https://www.x.org/releases/X11R7.7/doc/dri2proto/dri2proto.t...