User Jacques Foucry walks us through his journey of installing FreeBSD 12.0 on a Lenovo Thinkpad X280 notebook. He starts from configuring UEFI, rc.conf, hardware config, all the way to Xorg. See the link below for the full set of instructions. He wrote the entire guide in both French and English languages. Merci, Jax!
Full tutorial: https://adminblog.foucry.net/posts/info/freebsd-thinkpad/