JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" id="path" name="path" />
<input type="submit" id="submit" value="Change it" onclick="changePath()">
<embed id="embed1" type="application/x-bbx" src="/tmp/testfile.bbx"></embed>

JavaScript

function changePath() {
    var e = document.getElementById('path');
    var val = e.value;
    var embed1 = document.getElementById('embed1');
    embed1.src = val;
}