Feature Request

What problem are you trying to solve?

I start my day by running linkerd dashboard --show grafana and leaving my important dashboards opened on my secondary screen.

But from time to time, the port-forward issued by the linkerd dashboard command is cancelled. When that happens, I don't immediately notice because that terminal tab is hidden behind other windows.

And when I glance at my dashboard to make sure everything's running fine, I don't realize that I'm looking at stale data because the dashboard keeps displaying the last charts it was able to compute.

How should the problem be solved?

By displaying some sort of warning (yellow or red) on the dashboard to bring to my attention that the underlying Prometheus connection is broken and that my dashboard isn't able to auto-refresh anymore.