JSFiddle - React, Tailwind, and code Playground

HTML

<script type="text/javascript">
function test(string) {
        var match = /([\s"']+on\w+)\s*=/i.test(string);
        return match ? 'match :(' : 'bypass :)';
}
    var s=test('<img src="x"onerror =alert(1)>');
alert(s);
</script>