ArcaneChat on Nostr: that is a green area, the multi-relay feature was introduced this year just some ...

that is a green area, the multi-relay feature was introduced this year just some months ago, and while currently it is as you say, you need to send a message to them or even just reading their messages will do

but in the future this will work even without you needing to write to them

in practice one doesn't change relays so often tho, so if you write to them while you already have 3 relays, that is good enough because the chances of all the 3 relays/servers going down is unlikely