I can also confirm that 0.103-0ubuntu5~20.04.3 from focal-proposed fixes this bug.
root@xxx:~# dpkg -l | grep netplan
ii libnetplan0:amd64 0.103-0ubuntu5~20.04.3 amd64 YAML network configuration abstraction runtime library
ii netplan.io 0.103-0ubuntu5~20.04.3 amd64 YAML network configuration abstraction for various backends
root@xxx:~# netplan try
Warning: Stopping systemd-networkd.service, but it can still be activated by:
systemd-networkd.socket
Do you want to keep these settings?
Press ENTER before the timeout to accept the new configuration
Changes will revert in 118 seconds
Reverting.
Warning: Stopping systemd-networkd.service, but it can still be activated by:
systemd-networkd.socket
root@xxx:~# netplan try
Warning: Stopping systemd-networkd.service, but it can still be activated by:
systemd-networkd.socket
Do you want to keep these settings?
Press ENTER before the timeout to accept the new configuration
Changes will revert in 119 seconds
Configuration accepted.
I can also confirm that 0.103-0ubuntu5~ 20.04.3 from focal-proposed fixes this bug.
root@xxx:~# dpkg -l | grep netplan 20.04.3 amd64 YAML network configuration abstraction runtime library 20.04.3 amd64 YAML network configuration abstraction for various backends
ii libnetplan0:amd64 0.103-0ubuntu5~
ii netplan.io 0.103-0ubuntu5~
root@xxx:~# netplan try networkd. service, but it can still be activated by: networkd. socket
Warning: Stopping systemd-
systemd-
Do you want to keep these settings?
Press ENTER before the timeout to accept the new configuration
Changes will revert in 118 seconds networkd. service, but it can still be activated by: networkd. socket
Reverting.
Warning: Stopping systemd-
systemd-
root@xxx:~# netplan try networkd. service, but it can still be activated by: networkd. socket
Warning: Stopping systemd-
systemd-
Do you want to keep these settings?
Press ENTER before the timeout to accept the new configuration
Changes will revert in 119 seconds
Configuration accepted.