Fix stub zone operation when talking to minimal authoritative servers
#1736 (closed) was created to fix the issue that when the authoritative server to which a stub zone is pointing is configured for "minimal-responses yes;" and the NS are in-zone, operation of the stub zone would fail because it did not receive address records for the zone's NS in the Additional section of the NS response.
I believe that the fix was applied at the wrong end of the conversation, by making the authoritative server's response to NS queries return Additional data even if "minimal-responses" is set to "yes".
A BIND recursive server (with stub zones configured) may be talking to a non-BIND authoritative server with a more strict minimal response configuration, in which case the problem would still exist.
I think the correct fix would be to modify the stub zone code so that, if it needs address records for the given NS, it queries for them. This should work without any extra user configuration because stub zones must be defined with at least one primary - a bit like root hints - which is used to send the initial SOA and NS queries. The same address(es) can be used for the address queries for the NS records, given that they are in the zone itself.