Cannot create VPN connection: "Invalid setting General: connection.interface-name: '': interface name must not be empty"

A new VPN connection (vpnc in this case) can't be created, because validation rules are invalid. The "Add" button in GNOME applet and "Save" button in nm-connection-editor never get enabled.

** Message: 14:33:35.441: Cannot save connection due to error: Invalid setting VPN: IPSec ID
** Message: 14:33:49.288: Cannot save connection due to error: Invalid setting General: connection.interface-name: '': interface name must not be empty

Encountered on NM 1.37.90 on top of fc36 Beta, though Ubuntu 22.04 is affected too (https://bugs.launchpad.net/ubuntu/+source/network-manager-applet/+bug/1968588)

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