moongreet hardcodes /usr/share/wayland-sessions in src/sessions.rs and
greeter.rs calls get_sessions(None, None), so the default cannot be
overridden from config.
/etc/fonts/conf.d is owned by the NixOS fontconfig module and rejects
environment.etc entries. Same content as
defaults/etc/fonts/conf.d/65-moonarch-fonts.conf.
nevaforget