Uh, 6508675309@whatsapp or @signal If there is no account on that service, just like email, there would be a failure message but it should work. This is how

Uh, 6508675309@whatsapp or @signal If there is no account on that service, just like email, there would be a failure message but it should work. This is how mastodon or matrix does local handles vs federated handles. Simple @user for local and @local@server for outside.