Can microphone audio be synthesized when recording screen? about webm-muxer HOT 2 CLOSED

let audioContext = new AudioContext()

// Create MediaStreamSource nodes
let micStream = await navigator.mediaDevices.getUserMedia({ audio: true })
let micSource = audioContext.createMediaStreamSource(micStream)
let micGain = audioContext.createGain()

let displayStream = await navigator.mediaDevices.getDisplayMedia({ video: true, audio: true })
let displaySource = audioContext.createMediaStreamSource(displayStream)
let displayGain = audioContext.createGain()

// Create the MediaStreamDestination
let destination = audioContext.createMediaStreamDestination()

// Connect the microphone source to gain node and destination
micSource.connect(micGain)
micGain.connect(destination)

// Connect the display source to gain node and destination
displaySource.connect(displayGain)
displayGain.connect(destination)

// Set whatever volumes you want
micGain.gain.value = 1
displayGain.gain.value = 0.7

// Create the MediaStreamTrackProcessor
let trackProcessor = new MediaStreamTrackProcessor(destination.stream.getAudioTracks()[0])
let consumer = new WritableStream({
    write(audioData) {
        // Assuming the AudioEncoder and stuff are set up already
        audioEncoder.encode(audioData);
        audioData.close();
    }
});
trackProcessor.readable.pipeTo(consumer);