@Izno just to check I understand:

• By default in all skins except Minerva with safe mode enabled the font size of mw-tag-markers is 14px and the individual tags are 14px.
• By default in Minerva with safe mode enabled the font size of mw-tag-markers is 13.6px and the individual tags are 11.56px
• English Wikipedia applies font-size 90% which alters these to 12.6px

Is the request here, to standardize the size across skins AND to remove the English Wikipedia style (perhaps for example settling on 13px?) or just the former?

Attach your files!

By default in all skins except Minerva with safe mode enabled the font size of mw-tag-markers is 14px and the individual tags are 14px.

Vectors are 14px, Timeless is 15+, Monobook is 13-.

Is the request here, to standardize the size across skins AND to remove the English Wikipedia style (perhaps for example settling on 13px?) or just the former?

At minimum the first. This could be: don't make Minerva small, or it could be make everyone small. One of these might be easier, especially considering every other wiki and the differing font sizes already present between skins.

(I happened to use computed sizes rather than hunting down the chains of relative sizing going on here.)

English Wikipedia applies font-size 90% which alters these to 12.6px

In Minerva, it would make the font sizing 90% of 11.56px for the specific tags, which would be 10.4px. For the others, it is currently: Vectors 12.6px, Monobook 11.4px, Timeless 13.7px.

Okay thanks.

Honestly I'd like to get us to a solution where there is no need to override in wiki and these are not rendered at sub-pixel sizes. Loading a style that only applies to special pages for all page views is not good practice.

I don't really see Minerva being different as a bug - this seems like an intentional choice of font size made my a designer to make tags relatively smaller in comparison to the other elements, whereas for desktop for whatever reason no intentional choice has been made so the community has stepped in to do that which is inconsistent with mobile.

I would see this bug different and recommend upstreaming the styles from MediaWiki:Common.css to core to reduce the size of these in non-Minerva skins. Would that make sense? Note, Minerva has a skinStyle to intentionally override these defaults so shouldn't be impacted.

Upstreaming any size differences to the specific skins might make sense. I've come to the conclusion that putting them in core doesn't given the size differentials with the deployed skins and font size just generally being somewhat-intimately tied to the skin's level of control (though hopefully we may see the back of Monobook some day). A solid chunk of the fleet has duplicated the styles, presumably from English Wikipedia. They definitely weren't thinking about mobile, since those are categorically in Common.css with some Vector.css sprinkled in. Of the largest Wikipedia wikis, it looks like an even split of added and not-added styles though: en.wp, fr.wp, fa.wp, pt.wp, ru.wp, uk.wp, vi.wp have something added; these don't: ar.wp (the one in there is a false positive), arz.wp, de.wp, es.wp, it.wp, nl.wp, sv.wp, zh.wp. pl.wp does something wildly different with mobile.css but not anything else in Common.css, as a particular funny looking one.

The other thing that can't really be done about the block today anyway is upstreaming to core the use of italics, which our wikis opted into but Minerva doesn't really fit with its 'button' like tag appearance. (See also T147541#2714532 I guess regarding italics use for certain languages.) So I'd be adding something in the skin pages regardless on that point. (Which I did already, with font size selections also.)