Jitsi, getDisplayMedia() does not capture sound from the participant

Question

I am getting screen video and system sound stream from getdisplaymedia and getting mic stream from getusermedia,and recording these streams with MediaRecorder. mic and screen record are fine, all system sounds comes but jitsi participant voice not recording. Here is my code:

function openShareScreen() {

navigator.mediaDevices.getDisplayMedia({
    video: { displaySurface: "browser" },
    audio: true
}).then((desktopStream) => {
  
    let screenAudioTrack = desktopStream.getAudioTracks()[0];
    if (screenAudioTrack === undefined) {
        confirmSwalMessageConfirmOnly("Ses Paylaşımı Yapılmadı!", "Görüşme kaydı için lütfen görüntü ve ses paylaşımına izin veriniz!", "warning", openShareScreen);
        //recording = false;
        desktopStream.getTracks()
            .forEach(track => track.stop())
        return null;
    }

    var finalStream = new MediaStream();

    navigator.mediaDevices.getUserMedia({
        video: false, audio: true
    }).then((voiceStream) => {

        //Kamera ve mikrofon izin kontrolü yapılıyor
        navigator.permissions.query(
            { name: 'camera' },
            { name: 'microphone' }
        ).then(function (permissionStatus) {

            // granted, denied, prompt
            if (permissionStatus.state !== 'granted') {
                confirmSwalMessageConfirmOnly("Mikrofon/Kamera izni verilmedi!", "Görüşme kaydı için internet tarayıcınıza mikrofon ve kameraya erişim izni veriniz!", "warning", openShareScreen);
                //recording = false;
                desktopStream.getTracks().forEach(track => track.stop())
                voiceStream.getTracks().forEach(track => track.stop());
                return null;

            }
        })

        // important: we must convert multiple audio tracks into single audio track
        var mixedAudioStream = getMixedAudioStreamXYZ([voiceStream, desktopStream]) || microphone;

        mixedAudioStream.getAudioTracks().forEach(function (audioTrack) {
            finalStream.addTrack(audioTrack);
        });

        desktopStream.getVideoTracks().forEach(function (videoTrack) {
            finalStream.addTrack(videoTrack);
        });

        //Verilen time out interval süresinde kaydı başla
        var timeOutStopRecorder;
        recordLoop();

        function recordLoop() {
            
            recorder = new MediaRecorder(finalStream, { mimeType: 'video/webm', videoBitsPerSecond: glbVideoBitsPerSecond });

            recorder.ondataavailable = e => {

                if (e.data && e.data.size > 0) {
                    recordingData = [];
                    recordingData.push(e.data);

                }
            };

            recorder.onstop = () => {
                saveRecordDone = false;
                clearTimeout(timeOutStopRecorder);
                var blob = new Blob(recordingData, { type: 'video/webm' })
                console.log("Kayıt Diske Yazıldı:" + getDateTimeNow());
                SaveRecord(blob);
                recordLoop();
            };
            console.log("Kayıt Başladı:" + getDateTimeNow());
            recorder.start();
            timeOutStopRecorder = setTimeout(() => {
                console.log("Kayıt Durdu:" + getDateTimeNow());
                recorder.stop();
            }
                , 60000);
        }

        //recorder = RecordRTC(finalStream, {
        //    type: 'video',
        //    mimeType: "video/webm;codecs=vp8,opus",
        //    videoBitsPerSecond: glbVideoBitsPerSecond
        //});

        //recorder.startRecording();
        //recording = true;
        finalStream.getVideoTracks()[0].addEventListener('ended', () => {
            //stopRecordingAndSave();
            recorder.stop();
            confirmSwalMessageConfirmOnly("Paylaşım durduruldu!", "Görüşme kaydı için lütfen görüntü ve ses paylaşımına izin veriniz!", "warning", openShareScreen);
            //recording = false;
        });
    }).catch(err => {
        console.warn(err);
        confirmSwalMessageConfirmOnly("Mikrofon/Kamera izni verilmedi!", "Görüşme kaydı için internet tarayıcınıza mikrofon ve kameraya erişim izni veriniz!", "warning", openShareScreen);
        //recording = false;
    });
}).catch(err => {
    confirmSwalMessageConfirmOnly("Uyarı!", "Görüşme kaydı için lütfen görüntü ve ses paylaşımına izin veriniz!", "warning", openShareScreen);
    //recording = false;
});

}

function getMixedAudioStreamXYZ(arrayOfAudioStreams) {

var audioContext = new AudioContext();

var audioSources = [];

var gainNode = audioContext.createGain();
gainNode.connect(audioContext.destination);
gainNode.gain.value = 0; // don't hear self

var audioTracksLength = 0;
arrayOfAudioStreams.forEach(function (stream) {
    if (!stream.getAudioTracks().length) {
        return;
    }

    audioTracksLength++;

    var audioSource = audioContext.createMediaStreamSource(stream);
    audioSource.connect(gainNode);
    audioSources.push(audioSource);
});

if (!audioTracksLength) {
    return;
}

audioDestination = audioContext.createMediaStreamDestination();
audioSources.forEach(function (audioSource) {
    audioSource.connect(audioDestination);
});
return audioDestination.stream;

}