I can't boot FreeBSD UNIX 15 on Lenovo ThinkPad X1 Yoga (20SA), which GRUB 2 says 'error: not a directory'. That's from Slackware 15 so is from at most 2022, but I read maybe FreeBSD FFS/UFS slightly changed since then, like with journalling? Do I have to manually use an older type when making filesystem for installation (and how) so GRUB 2 can boot FreeBSD? It boots fine on one older and one newer model similar ThinkPad though those had FreeBSD 14 and older and were upgraded.