Connection: fallback on g1.duniter.org:443

I wanted to add a local connection to localhost:10901 Duniter node. But few time later, I closed my node and Cesium. And then I want to open Cesium again, without success as my localhost:10901 is down.

It would be very nice if Cesium could automatically detect that the connexion is lost with localhost and tests the connection with a fallback node like g1.duniter.org:443, and temporarily uses it.

So for example, in my case I would be asked:

Votre nœud `localhost:10901` est inaccessible, voulez-vous temporairement utiliser le nœud `g1.duniter.org:443` à la place ?

And then if I relaunch Cesium and my Duniter node is UP, Cesium would automatically be back again on localhost:10901, because g1.duniter.org:443 was just a session connection.

Maybe you could use sessionStorage instead of localStorage for that purpose.