If you recently had your FreeBSD 12.1 running ThinkPad X250 (or any other laptop with a Intel GPU) crashing systematically on boot, it may be because of the i915kms module from the graphics/drm-kmod port. If you did install this or drm-fbsd12.0-kmod through the packages, you should know that the binary package is only compatible with FreeBSD 12.0. If you want this to work (that is, not to cause a kernel panic), you should compile the port manually [1]. In other words:
portsnap fetch update cd /usr/ports/graphics/drm-fbsd12.0-kmod make install clean