<html><head></head><body><div style="font-family: Verdana;font-size: 12.0px;"><div>I did some further research: The WHATWG spec differs from the Mozilla definition. It lists <sup> and <sup> in the text-level semantics section and states:</div>
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<div>> These elements must be used only to mark up typographical conventions with specific meanings, not for typographical presentation for presentation's sake.</div>
<div>> The sub element can be used inside a var element, for variables that have subscripts.</div>
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<div>See also: https://html.spec.whatwg.org/multipage/text-level-semantics.html#the-sub-and-sup-elements</div>
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<div>Rergards,</div>
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<div>Marius Spix</div>
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<div style="margin:0 0 10px 0;"><b>Gesendet:</b> Montag, 22. März 2021 um 18:37 Uhr<br/>
<b>Von:</b> "Marius Spix" <marius.spix@web.de><br/>
<b>An:</b> christoph.paeper@crissov.de<br/>
<b>Cc:</b> unicode@unicode.org<br/>
<b>Betreff:</b> Aw: Re: HTML entities</div>
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<div>Dear Christoph,</div>
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<div>according to Mozilla [1],</div>
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<div>> The <sup> element should only be used for typographical reasons—that is, to change the position of the text to comply > with typographical conventions or standards, rather than solely for presentation or appearance purposes.</div>
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<div>[1] <a href="https://developer.mozilla.org/en-US/docs/Web/HTML/Element/sup" target="_blank">https://developer.mozilla.org/en-US/docs/Web/HTML/Element/sup</a></div>
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<div>Regards,</div>
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<div>Marius Spix</div>
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<div style="margin: 0 0 10.0px 0;"><b>Gesendet:</b> Montag, 22. März 2021 um 18:17 Uhr<br/>
<b>Von:</b> "Christoph Päper via Unicode" <unicode@unicode.org><br/>
<b>An:</b> unicode@unicode.org<br/>
<b>Betreff:</b> Re: HTML entities</div>
<div>Marius Spix via Unicode <unicode@unicode.org>:<br/>
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> CSS is also no solution, because <sub> and <sub> are semantic tags (like <del>, <strong>, <em> and <kbd>) and not just stylistic ones (like <s>, <b>, <i> or <tt>).<br/>
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When HTML introduced the `b`/`strong` and `i`/`em` distinctions, it should also have added presentational/semantic pairs<br/>
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- `sup`/`exp` (exponent) or `pow` (power) and<br/>
- `sub`/`idx`, `ind` (index) or `base`.<br/>
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I don’t think the WHATWG or W3C would be interested in adding them now.<br/>
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