JSFiddle - React, Tailwind, and code Playground
HTML
<input type="text" name="var[list]" id="ixv[list]" value="foo">
JavaScript
alert(document.getElementById('ixv[list]').value);
<input type="text" name="var[list]" id="ixv[list]" value="foo">
alert(document.getElementById('ixv[list]').value);