The HTMLCanvasElement.captureStream() method returns a CanvasCaptureMediaStream that is a real-time video capture of the surface of the canvas.
The MediaRecorder.stream read-only property returns the stream that was passed into the MediaRecorder() constructor when the MediaRecorder was created.
The read-only property MediaStreamTrack.readyState returns an enumerated value giving the status of the track.
The MediaStreamTrack.stop() method stops playing the source associated with the track. Both the source and the track are deassociated. The track state is set to ended.
The clone() method of the MediaStream interface creates a duplicate of the MediaStream. This new MediaStream object has a new unique id and contains clones of every MediaStreamTrack contained by the MediaStream on which clone() was called.