[jlreq] Unable to make list counters stand upright in vertical text (#170)

r12a has just created a new issue for https://github.com/w3c/jlreq:

== Unable to make list counters stand upright in vertical text ==
A common way to orient counters for lists in vertical text is to have an upright number with a dot alongside it.<a href="https://w3c.github.io/i18n-drafts/articles/vertical-text/index-data/tcu-all-pref.html" target="text"></a>

![vertical-lists](https://user-images.githubusercontent.com/4839211/73653505-33159780-4681-11ea-9b21-0c036e0a4d45.png)

The expected way to achieve this in HTML would be to use the following CSS: <code>li::marker { text-combine-upright: all; }</code>, however this cannot be used because browsers don't support <code class="kw" translate="no">text-combine-upright</code>. Tests: <a href="https://w3c.github.io/i18n-drafts/articles/vertical-text/index-data/japanese_list_upright.html" target="text">standard syntax</a> • <a href="https://w3c.github.io/i18n-drafts/articles/vertical-text/index-data/japanese_list_upright_pref.html" target="text">proprietary syntax</a>

A workaround might be to use fullwidth characters for counters, such as ①, ②, ③ etc., but use of such a workaround requires the availability of custom built counter styles, and only Firefox currently supports the CSS Counter Styles specification. So that doesn't work either. Tests: <a href="https://w3c.github.io/i18n-drafts/articles/vertical-text/index-data/korean-list-counterstyles.html" target="text">standard syntax</a> • <a href="https://w3c.github.io/i18n-drafts/articles/vertical-text/index-data/korean-list-counterstyles-pref.html" target="text">proprietary syntax</a>

It is a significant nuisance for content authoring to not be able to produce upright counters for lists.

Please view or discuss this issue at https://github.com/w3c/jlreq/issues/170 using your GitHub account