I have successfully upgraded the FreeBSD (actually NomadBSD) installed on a Lenovo ThinkPad T450 from 12.2-RELEASE-p3. After upgrading all packages I have replaced the package graphics/drm-fbsd12-kmod with graphics/drm-fbsd13-kmod. After rebooting the laptop works but the Xorg server is slow because it uses a lot of CPU: moving a window around the screen uses 100% of the CPU. Regards, Maurizio