I think the manual is behind:
$ unwind -nvf/dev/null preference { DoT oDoT-forwarder forwarder recursor oDoT-dhcp dhcp stub } OK? Index: unwind.conf.5 =================================================================== RCS file: /cvs/src/sbin/unwind/unwind.conf.5,v retrieving revision 1.24 diff -u -p -r1.24 unwind.conf.5 --- unwind.conf.5 29 Oct 2020 17:28:12 -0000 1.24 +++ unwind.conf.5 26 Dec 2020 16:48:59 -0000 @@ -123,7 +123,7 @@ itself recursively resolves names. .El .Pp The default preference is -.Ic DoT forwarder recursor dhcp stub . +.Ic DoT oDoT-forwarder forwarder recursor oDoT-dhcp dhcp stub . .It Ic force Oo Cm accept bogus Oc Ar type Brq Ar name ... Force resolving of .Ar name