Indication of lost sensor in frontend

Hello,

I’m starting to discover HA.

I have several rfx , mqtt of configured sensors.
Is it not possible to display in the “frontend” that a sensor" is lost after a given time?

For example, display the last value in red to report a problem?

thanks,

They can show as “unavailable” if you set an LWT (last will and testament) message in your mqtt devices.

You could use Entity filter card to show the sensors only when they have a state of “Unknown”

Thank you for your feedback,

With “Entity filter card”, I can see my sensor in an “unknown” state appearing in the “card”.

However, I did not find in the documentation the delay the status of a sensor changes to “unknown” if not received

Use

expire_after: 120

In your sensor config yaml
Time is in seconds