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Empty resolv.conf on wireguard disconnect

NetworkManager fails to restore underlying connections resolv.conf content on WireGuard disconnect.

State before WireGuard connection:

$ nmcli
wlp0s20f3: connected to RT-5_KV3
        "Intel Cannon Point-LP CNVi"
        wifi (iwlwifi), 20:79:18:64:53:B6, hw, mtu 1500
        ip4 default
        inet4 192.168.0.15/24
        route4 0.0.0.0/0
        route4 192.168.0.0/24
        inet6 fe80::2e27:438c:a0ff:7ff0/64
        route6 fe80::/64
        route6 ff00::/8

p2p-dev-wlp0s20f3: disconnected
        "p2p-dev-wlp0s20f3"
        wifi-p2p, hw

lo: unmanaged
        "lo"
        loopback (unknown), 00:00:00:00:00:00, sw, mtu 65536

DNS configuration:
        servers: 192.168.0.1
        domains: IGD_Rostelecom
        interface: wlp0s20f3

Proper upstream settings are passed into resolv.conf by NetworkManager:

$ cat /etc/resolv.conf 
# Generated by NetworkManager
search IGD_Rostelecom
nameserver 192.168.0.1

State after WireGuard connection with nmcli connection up wg0:

$ nmcli
wlp0s20f3: connected to RT-5_KV3
        "Intel Cannon Point-LP CNVi"
        wifi (iwlwifi), 20:79:18:64:53:B6, hw, mtu 1500
        ip4 default
        inet4 192.168.0.15/24
        route4 0.0.0.0/0
        route4 192.168.0.0/24
        inet6 fe80::2e27:438c:a0ff:7ff0/64
        route6 fe80::/64
        route6 ff00::/8

wg0: connected to wg0
        "wg0"
        wireguard, sw, mtu 1500
        inet4 10.200.200.3/24
        route4 10.200.200.0/24
        route4 0.0.0.0/0

p2p-dev-wlp0s20f3: disconnected
        "p2p-dev-wlp0s20f3"
        wifi-p2p, hw

lo: unmanaged
        "lo"
        loopback (unknown), 00:00:00:00:00:00, sw, mtu 65536

DNS configuration:
        servers: 1.1.1.1
        interface: wg0
        type: vpn

        servers: 192.168.0.1
        domains: IGD_Rostelecom
        interface: wlp0s20f3

Once again proper resolv.conf settings are filled by NetworkManager

$ cat /etc/resolv.conf 
# Generated by NetworkManager
nameserver 1.1.1.1

After nmcli connection down wg0 name resolution is completely broken, resolv.conf is empty:

$ cat /etc/resolv.conf 
# Generated by NetworkManager
$ nmcli
wlp0s20f3: connected to RT-5_KV3
        "Intel Cannon Point-LP CNVi"
        wifi (iwlwifi), 20:79:18:64:53:B6, hw, mtu 1500
        ip4 default
        inet4 192.168.0.15/24
        route4 0.0.0.0/0
        route4 192.168.0.0/24
        inet6 fe80::2e27:438c:a0ff:7ff0/64
        route6 fe80::/64
        route6 ff00::/8

p2p-dev-wlp0s20f3: disconnected
        "p2p-dev-wlp0s20f3"
        wifi-p2p, hw

lo: unmanaged
        "lo"
        loopback (unknown), 00:00:00:00:00:00, sw, mtu 65536

DNS configuration:
        servers: 192.168.0.1
        domains: IGD_Rostelecom
        interface: wlp0s20f3

Expected behavior: Restore underlying connections resolv.conf settings upon WireGuard disconnect

networkmanager version 1.30.2-1

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