I agree with the change @GeekSmith suggests as well.
I'm running a system without network-manager, without netplan, without resolvconf. Only ifupdown and dhclient. I expect /etc/resolv.conf to be updated by the logic in /sbin/dhclient-script where it (correctly, in my system) assumes it is the only source of dns servers. I have reopened the bug.
I agree with the change @GeekSmith suggests as well.
I'm running a system without network-manager, without netplan, without resolvconf. Only ifupdown and dhclient. I expect /etc/resolv.conf to be updated by the logic in /sbin/dhclient- script where it (correctly, in my system) assumes it is the only source of dns servers. I have reopened the bug.