document.querySelector() with .value code example
Example: document.queryselector
<div id="foo\bar"></div>
<div id="foo:bar"></div>
<script>
console.log('#foo\bar'); // "#fooar" (\b is the backspace control character)
document.querySelector('#foo\bar'); // Does not match anything
console.log('#foo\\bar'); // "#foo\bar"
console.log('#foo\\\\bar'); // "#foo\\bar"
document.querySelector('#foo\\\\bar'); // Match the first div
document.querySelector('#foo:bar'); // Does not match anything
document.querySelector('#foo\\:bar'); // Match the second div
</script>