Try messaging
This is Glitr’s conversation path with two mailboxes: connect, add a contact by repo URL, send, poll, watch ticks, and — if both sides stay open — go Live.
Fullscreen hides extra chrome so it feels like the app. Use two browser tabs. Follow Your first conversation with those tabs as Alex and Blair.
You will need two git remotes and tokens, the same as production. That is the point: there is no fake network in the middle.
When you are done, live vs offline explains what you just saw.