Problem:
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255057
Solution:
- Download DVD ISO.
- # mdconfig -f FreeBSD-13.0-RELEASE-amd64-dvd1.iso
- # mount_cd9660 /dev/mdX /media
- copy contents to folder.
- remove any files you don't want - in my case, all 32 bit binaries. I only run 64 bit code.
mkisofs to create a new ISO file.
- burn CD from this new, slightly smaller ISO file.
If you don't have mkisofs ...
# pkg install cdrtools