JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <svg id="mysvg" viewBox="0 0 100 100" width="100px" height="10px"></svg>    
    <div id="method1">Method 1 : <span></span></div>
    <div id="method2">Method 2 : <span></span></div>
    <div id="method2">Method 3 : <span></span></div>
</body>

JavaScript

var svg = document.getElementById("mysvg");
$("#method1 > span").html(svg.getAttribute("viewBox"));
$("#method2 > span").html($("#mysvg").attr("viewBox"));
$("#method3 > span").html($(svg).attr("viewBox"));