(Lib)Linphone / belle-sip tries DNS lookup, when it must not

[systemcrash]

Linphone SIP REGISTERs to Proxy A. Using a fake domain "ig" -

So:
SIP Addr: sip:user2@ig
Server: sip:10.10.10.1;transport=udp
Transport: UDP

( does not matter what we put in the Route field )

Linphone can REGISTER without a DNS lookup - why must it send a DNS lookup for an INVITE, which is not unsolicited? This is wrong. If REGISTERed to a Proxy, or domain, no DNS lookup is necessary (Domain/proxy will perform this).

The correct procedure is to perform a DNS lookup of the Server: DNS name - not on the domain portion of the R-URI.

...
2020-09-11 15:37:36:981 [linphone/liblinphone] MESSAGE Contact has been fixed using proxy
2020-09-11 15:37:36:982 [linphone/liblinphone] MESSAGE [sip:user2@ig] calling [sip:2065085852@ig] on op [0x7fabc47d1590]
2020-09-11 15:37:36:982 [linphone/belle-sip] MESSAGE transaction [0x6000038f9450]: starting transaction background task with id=[36d].
2020-09-11 15:37:36:982 [linphone/belle-sip] MESSAGE belle_sip_client_transaction_send_request(): waiting channel to be ready
2020-09-11 15:37:36:982 [linphone/belle-sip] MESSAGE channel [0x7fabc4eec000]: starting send background task with id=[36e].
2020-09-11 15:37:36:982 [linphone/belle-sip] MESSAGE channel [0x7fabc4eec000]: starting resolution of ig
2020-09-11 15:37:36:982 [linphone/belle-sip] MESSAGE channel 0x7fabc4eec000: state RES_IN_PROGRESS
2020-09-11 15:37:36:982 [linphone/belle-sip] MESSAGE transaction [0x6000038f9450] channel state changed to [RES_IN_PROGRESS]
2020-09-11 15:37:36:983 [linphone/belle-sip] MESSAGE Resolver is using DNS server(s):
2020-09-11 15:37:36:983 [linphone/belle-sip] MESSAGE 	192.168.19.1
2020-09-11 15:37:36:983 [linphone/belle-sip] MESSAGE 	fdc8:efdb:a944::1
2020-09-11 15:37:36:983 [linphone/belle-sip] MESSAGE Resolver is not using connect().
2020-09-11 15:37:36:983 [linphone/belle-sip] MESSAGE resolver_process_data dns_res_check() in progress
2020-09-11 15:37:36:983 [linphone/belle-sip] MESSAGE DNS resolution awaiting response, queued to main loop
2020-09-11 15:37:36:983 [linphone/liblinphone] MESSAGE CallSession [0x60000298e6b8] moving from state LinphoneCallOutgoingInit to LinphoneCallOutgoingProgress
2020-09-11 15:37:36:983 [linphone/liblinphone] MESSAGE Linphone core [0x7fabbf120200] notified [call_state_changed]
...

belle-sip tries: _sip._udp.ig: type SRV, class IN
gets: Flags: 0x8183 Standard query response, No such name
tries: _sip._udp.ig.lan: type SRV, class IN
gets: Flags: 0x8183 Standard query response, No such name
tries: ig.lan: type A, class IN
gets: Flags: 0x8183 Standard query response, No such name
tries: ig: type A, class IN
gets: Flags: 0x8183 Standard query response, No such name

The only way this scenario ever works is via TLS.

This bad behaviour exists in Linphone 4.1.1, 4.2.2, etc - where is the failure? (lib)Linphone or belle-sip?