with org-html-html5-fancy is non-nil, images are exported with something like this code:
<figure>
<p><img src="
https://imgs.xkcd.com/comics/proof_2x.png" alt="proof_2x.png" class="fragment (appear) visible current-fragment" data-fragment-index="0"></p>
</figure>
At least in ox-reveal, this makes it quite difficult to address images separately from text (e.g., to set the text-align property appropriately. You can try this if you have ox-reveal installed with any simple image:
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