Comment 22 for bug 1959570

I tested netplan.io 0.104-0ubuntu2~20.04.4 from ppa:slyon/lp1959570 (which is the same upload as in focal-proposed), TestCase 1 (building a core20 snap & Ubuntu Core image from that PPA). Everything worked as expected, no crashes observed.

# This change is only available in the latest upload from focal-proposed:
slyon@ubuntu:~$ cat /usr/share/netplan/netplan/cli/core.py | grep "snap/bin"
FALLBACK_PATH = '/usr/bin:/snap/bin'

slyon@ubuntu:~$ snap install network-manager --channel=20/stable
network-manager (20/stable) 1.22.10-22 from Canonical✓ installed
slyon@ubuntu:~$ nmcli # VERIFY br54 is not there
ens3: connected to netplan-ens3
        "ens3"
        ethernet (virtio_net), 52:54:00:12:34:56, hw, mtu 1500
        ip4 default
        inet4 10.0.2.15/24
        route4 0.0.0.0/0
        route4 10.0.2.0/24
        inet6 fe80::5054:ff:fe12:3456/64
        route6 fe80::/64

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

DNS configuration:
        servers: 10.0.2.3
        interface: ens3

Use "nmcli device show" to get complete information about known devices and
"nmcli connection show" to get an overview on active connection profiles.

Consult nmcli(1) and nmcli-examples(7) manual pages for complete usage details.
slyon@ubuntu:~$ sudo snap set system system.network.netplan.network.bridges.br54.dhcp4=true
slyon@ubuntu:~$
slyon@ubuntu:~$
slyon@ubuntu:~$
slyon@ubuntu:~$
slyon@ubuntu:~$
slyon@ubuntu:~$
slyon@ubuntu:~$
slyon@ubuntu:~$
slyon@ubuntu:~$
slyon@ubuntu:~$ netplan get # VERIFY br54 is there
network:
  version: 2
  renderer: NetworkManager
  ethernets:
    ens3:
      dhcp4: true
  bridges:
    br54:
      dhcp4: true
slyon@ubuntu:~$ sudo journalctl | grep FileNotFound # EMPTY => no errors
slyon@ubuntu:~$ nmcli # VERIFY br54 is there
ens3: connected to netplan-ens3
        "ens3"
        ethernet (virtio_net), 52:54:00:12:34:56, hw, mtu 1500
        ip4 default
        inet4 10.0.2.15/24
        route4 0.0.0.0/0
        route4 10.0.2.0/24
        inet6 fe80::5054:ff:fe12:3456/64
        route6 fe80::/64

br54: connecting (getting IP configuration) to netplan-br54
        "br54"
        bridge, 96:B7:B7:F3:2A:FB, sw, mtu 1500

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

DNS configuration:
        servers: 10.0.2.3
        interface: ens3

Use "nmcli device show" to get complete information about known devices and
"nmcli connection show" to get an overview on active connection profiles.

Consult nmcli(1) and nmcli-examples(7) manual pages for complete usage details.