preso/themes/reveal-hugo/exampleSite/layouts/partials/home/reveal-hugo/body.html

<!-- This partial is included before the end of the body tag for only the 'example' presentation -->
<!-- A common use would be to add JavaScript to the page to customize interactions -->
<!-- The Reveal.js JavaScript API is located at https://github.com/hakimel/reveal.js/#api -->
<script type="text/javascript">
// Log the current slide to the console when it changes
Reveal.addEventListener('slidechanged', function(event) {
  console.log("🎞️ Slide is now " + event.indexh);
});
</script>