example1.js

const pc = new RTCPeerConnection()

// 1. addTransceiver('audio')
const transceiver1 = pc.addTransceiver('audio')

// 2. negotiate
const offer1 = await pc.createOffer()
await pc.setLocalDescription(offer1)
await pc.setRemoteDescription(answer1)

// 3. stop()
transceiver1.stop()

// 4. negotiate
//
//    o  If an RtpTransceiver has been stopped and is associated with an m=
//       section, and the m= section is not being recycled as described
//       above, an m= section MUST be generated for it with the port set to
//       zero and all "a=msid" lines removed.
//
const offer2 = await pc.createOffer()
await pc.setLocalDescription(offer2)
await pc.setRemoteDescription(answer2)

// 5. addTransceiver('audio')
const transceiver2 = pc.addTransceiver('audio')

// 6. negotiate
//
//    o  If any RtpTransceiver has been added, and there exists an m=
//       section with a zero port in the current local description or the
//       current remote description, that m= section MUST be recycled by
//       generating an m= section for the added RtpTransceiver as if the m=
//       section were being added to the session description (including a
//       new MID value), and placing it at the same index as the m= section
//       with a zero port.
//
// `offer3` contains one m= section, and `pc.getTransceivers()` returns two
// RTCRtpTransceivers.
const offer3 = await pc.createOffer()
await pc.setLocalDescription(offer3)
await pc.setRemoteDescription(answer3)