Result cant show up in console log

[Bryan-snw]

so everything work just as fine, but i cant display res result in console log, but it show if i change it to alert, any tips?

<script type="text/javascript"> let scanner = new Instascan.Scanner({ video: document.getElementById('preview') }); scanner.addListener('scan', function (content) { console.log(content); alert(content); }); Instascan.Camera.getCameras().then(function (cameras) { if (cameras.length > 0) { scanner.start(cameras[0]); } else { console.error('No cameras found.'); } }).catch(function (e) { console.error(e); }); </script>