I see log entries for unbound that it is failing to create an ipv6 route.
2021-05-10T22:08:03 opnsense[16261] /services_unbound.php: The command '/sbin/route add -host -'inet6' '2a07:a8c1::b8:23a7' 'fe80::82e0:1dff:fe02:8019%'' returned exit code '71', the output was 'route: fe80::82e0:1dff:fe02:8019%: Name does not resolve'
I think that fe80::82e0:1dff:fe02:8019% should have been in my case fe80::82e0:1dff:fe02:8019%igb0
When I look in the Status Routes, I see routes for the ipv4 DNS servers I am using but not the ipv6 DNS servers.
It seems to work ok though, so is this a problem?