How to Make Light indicate No-VPN connection Active?
Izzy's idea about using Tasker for the task in chat


  A raw idea (not checked/verified) would be using an automation tool like Tasker and have it shutdown all network interfaces whenever VPN connection "got lost" (of course giving you a "manual backdoor", i.e. if you manually enable networking it shouldn't shut it down immediately again just because no VPN is active ;)


Solution


Create VPN profile in Settings > More > VPN
Attach it to Tasker


Feature-request: enable the front light configuration in the VPN menu