DNS Resolver: prevent OPNsense to add himself

[CDuv]

My OPNsense server has many interfaces (LAN, LAN_GUEST, LAN_GUEST2) and DNS Resolver is used by machines of LAN network.
I have another DNS server running elsewhere to handle my "local" domain and DNS Resolver is set to use this server as a domain override for "domain.lan".
This "domain.lan" zone has a A record for ""opnsense.domain.lan"
However, if any LAN machine where to ask the IP of "opnsense.domain.lan" to DNS Resolver it would respond with all the IP addresses of any interfaces (LAN, WAN, etc.) OPNsense has.

I get that OPNsense is:

• Not using domain overrides settings when asked about it's own FQDN
• Adding itself to DNS Resolver

If point 1 is abnormal: I'll create an issue on the bug tracker.
Is there a way to avoid/disable point 2?