revealjs-tweak.html

<script type="text/javascript">
  Reveal.on('ready', (event) => {
    if (event.indexh === 0) {
        document.querySelector("div.has-logo > img.slide-logo").style.display = "none";
    }
    // tweak r-vtack with image
    var slides = Reveal.getSlidesElement();
    slides.querySelectorAll('div.r-vstack').forEach((vstack) => {
      // check all chidren is a p tag
      var isAllP = Array.from(vstack.children).every((child) => child.tagName === 'P');
      // check all children of childre is an img tag
      var isAllImg = Array.from(vstack.children).every((child) => Array.from(child.children).every((child) => child.tagName === 'IMG'));
      if (isAllP && isAllImg) {
        // move all img to the root of vstack, and remove p
        Array.from(vstack.children).forEach((child) => {
          Array.from(child.children).forEach((img) => {
            vstack.appendChild(img);
          });
          vstack.removeChild(child);
        });
      }
    });
  });
  Reveal.addEventListener('slidechanged', (event) => {
    if (event.indexh === 0) {
      document.querySelector("div.has-logo > img.slide-logo").style.display = "none";
    }
    if (event.indexh === 1) { 
      document.querySelector("div.has-logo > img.slide-logo").style.display = null;
    }
  });
</script>