The Live Chat block is a simple, flowing message stream between your app's signed in visitors, distinct from the Comments block, comments are a threaded, permanent archive under a topic, Live Chat is closer to a group chat room, messages appear instantly for everyone with the page open.
Rooms
Live Chat's room setting works the same way Comments' topic does, every Live Chat block sharing the same room name shows the same conversation, leave it empty for one shared room across your whole app, or give different pages their own room to keep them separate.
Presence
Turn on "Show who is here right now" on a Live Chat block, or add a standalone Presence Indicator block, to show how many signed in visitors are currently active. Point a Presence Indicator at the same room as a Live Chat block to show who's in that specific conversation, or leave its room empty to track your whole app instead.
Tip: Both features require being logged in, a flowing conversation and a live headcount aren't meant to be a public, unauthenticated view, unlike Comments' own public read access.