Live mode

Live mode is replaying a session while it is still being recorded: events stream from the user's browser to a viewer with a short buffer delay, so support or engineering can watch a session in progress. In rrweb it is enabled with the replayer's `liveMode` option and started with `startLive()`.

How it works

The recorder's emit callback forwards events continuously, typically over a WebSocket (see WebSocket ingest), and the live replayer applies them as they arrive rather than from a completed array, trailing real time by a configurable buffer to absorb network jitter. The live mode recipe documents liveMode and startLive(). A viewer joining mid-session needs a recent full snapshot to start from, which is where checkouts earn their storage cost. Combined with the canvas WebRTC plugin, live mode extends to watching canvas-heavy apps in real time.

Where you encounter it

Live support and co-browsing workflows, operations dashboards watching high-value sessions, and agent supervision, where a human watches an automated browser session as it runs.