Video track not played - Githubissues

Hello i try to add audio track to file with only video track but after file saved, video track does not play i have tried load and save files and it is bad after save(just few KB) here is my code


<html>
  <script src="mp4box.all.js" ></script>
    <body>
        <script>
            function makeRequest(method, url) {
                return new Promise(function (resolve, reject) {
                    let xhr = new XMLHttpRequest();
                    xhr.responseType = 'arraybuffer';
                    xhr.open(method, url);
                    xhr.onload = function () {
                        if (this.status >= 200 && this.status < 300) {
                            resolve(xhr.response);
                        } else {
                            reject({
                                status: this.status,
                                statusText: xhr.statusText
                            });
                        }
                    };
                    xhr.onerror = function () {
                        reject({
                            status: this.status,
                            statusText: xhr.statusText
                        });
                    };
                    xhr.send();
                });
            }

            function loadFromBuffer(file, buffer) {
                return new Promise(function (resolve, reject) {
                    file.onError = function(e) {
                        reject(e);
                    };
                    file.onReady = function(info) {
                        resolve(info);
                    };
                    let tempBuffer = buffer;
                    tempBuffer.fileStart = 0;
                    if (!tempBuffer.fileStart) {
                        // IE does not support adding properties to an ArrayBuffer generated by XHR
                        tempBuffer = buffer.slice(0);
                        tempBuffer.fileStart = 0;
                    }
                    file.appendBuffer(tempBuffer, true);
                    file.flush();
                });
            }

            var videoUrl = "./video.mp4";

            async function start() {

                let videoBuffer = await makeRequest("GET", videoUrl); 
                let videofile = MP4Box.createFile();
                let videoInfo = await loadFromBuffer(videofile, videoBuffer);     

                videofile.save("test.mp4");
            }

            start();   
        </script>
    </body>
</html>
``
sample vido but i also try other videos same problem
https://user-images.githubusercontent.com/5040118/156850576-c539ede5-865c-404e-8ed6-447483190162.mp4

`

gpac / mp4box.js

Video track not played #273