I had a look at the source to try to help with your snapd branch, and it looks like the netplan D-Bus service is properly trying to terminate the helper process, which however is not handling SIGUSR1 properly. A comment in the source code explains the issue:
I had a look at the source to try to help with your snapd branch, and it looks like the netplan D-Bus service is properly trying to terminate the helper process, which however is not handling SIGUSR1 properly. A comment in the source code explains the issue:
https:/ /github. com/canonical/ netplan/ blob/main/ src/dbus. c#L101- L115