Icon On mouse over window


I made a graph in a Grafana panel to see the PV yield.

In the PostgreSQL DB while I grab the PV values I also write weather info and the relative icon. Icons have the name of three char string:
stands for the icon at the URL

It would be neat to show the icon in the window that appears whit the values when you move the mouse over the graph.

I could eventually predownload the icons so I have all of them locally.

How can I do that?