It would be nice to make subscript and superscript work in comments.
Here, these work :
In comments, these fail.
That doesn't work because HTML is not supported in comments. It has been suggested on Meta Stack Exchange to enable it in comments, but it got declined. See this answer from Jeff Atwood ♦
We do allow very limited markdown in comments now. Click the "help" link below the Add Comment button to get comment formatting help.
_for bold, italic
``for code blocks
[example](http://example.com "merely an example")
No HTML, just Markdown in comments, please!
Or, if you really need it, use Unicode subscript/superscript characters, as I demonstrated in my comment.
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