webkitGetUserMedia audio + video window

I have found a solution. Read here: muaz-khan/RecordRTC#181

Here is a code that starts to record video+audio in Electron:

let recorder;
let blobs = [];

function captureScreenVideoWithAudio() {
  navigator.webkitGetUserMedia({
    audio: true
  }, function(audioStream) {
    navigator.webkitGetUserMedia({
      audio: false,
      video: {
        mandatory: {
          chromeMediaSource: 'screen',
          minWidth: 1280,
          minHeight: 720
        }
      }
    }, handleVideoStream(audioStream), handleUserMediaError);
  }, function() {});
}

function handleVideoStream(audioStream) {
  return function(videoStream) {
    if (audioStream) {
      let audioTracks = audioStream.getAudioTracks();
      if (audioTracks.length > 0) {
        videoStream.addTrack(audioTracks[0]);
      }
    }
    recorder = new MediaRecorder(videoStream);
    blobs = [];
    recorder.ondataavailable = function(event) {
      blobs.push(event.data);
    };
    recorder.start();
  };
}

function handleUserMediaError(e) {
  console.error('handleUserMediaError', e);
}