Add "Sponsor" to a page

snippet.html

<!-- place the following line where you want the sponsor message to appear -->
<span class="s-message"></span>

<!-- place the following right before the </body> tag in the footer -->
<script>
$(document).ready(function () {
    var message = "Sponsor",
        target = $(".s-message");
    
    // Check if there is that class on the page
    if (target[0] != undefined) {
        target.text(message);
    }
});
</script>

Bugfix added.