Representation of stale/disconnected Things?

Hi! Does WebThings have the concept for a stale/disconnected device, and if so does the Gateway have a visual indication (like a grayed out Thing) of that state? I ask because I have a Zigbee temperature sensor whose temperature is definitely out of date, likely because it’s been days since the Gateway has gotten a message from it, but the Thing doesn’t have any indication of a problem. I’m interested in determining if that’s a bug, or simply just functionality not implemented/supported yet. If it’s a simple thing I may attempt implementing it myself :slight_smile:

With SmartThings it grays out the device, changes the state label to “Offline”, and on the detail view has a message saying “Device disconnected.\nCheck to see if the device has power and is operating normally. If the device is still disconnected, try adding the device to SmartThings again”

Yes if thing is not pingable its UI is greyed and I dont think you can interact with…
May a property with last updated time would help ? or should this be done in HTTP header ?