Authoring sub/super-scripts for translation
HTML
<h3>
Original:
</h3>
<p>
So much CO<sub>2</sub> per km<sup>2</sup>...
</p>
<h3>
Translation-friendly:
</h3>
<p>
So much CO₂ per km²...
</p>
JavaScript
const bodyText = document.body.innerHTML
restoredBody = bodyText.replace(/²/g, '<sup>2</sup>');
restoredBody = restoredBody.replace(/₂/g, '<sub>2</sub>');
document.body.innerHTML = restoredBody