Running the latest stable/13-n245952-7cddc353b63c with virtualbox installed and vboxnet_enable="YES"
When trying to boot the system up, the system hangs on trying to run /usr/local/etc/rc.d/vboxnet
Hitting ctrl+c interrupts the script and system continues to boot. Narrowed it down to kldload vboxnetflt hanging.
See slightly more recent bug 256505
Marking this one as duplicate since discussion is already happening in bug 256505
*** This bug has been marked as a duplicate of bug 256505 ***