[jlreq] Tate-chu-yoko lacks support for digits value (#169)

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

== Tate-chu-yoko lacks support for digits value ==
The CSS <code class="kw" translate="no">text-combine-upright</code> property works with the <code class="kw" translate="no">all</code> value in all major browsers, although for <span class="partial">legacy Edge</span> you need to use the proprietary property <code class="kw" translate="no">-ms-text-combine-horizontal</code>. Tests:  <a href="https://w3c.github.io/i18n-drafts/articles/vertical-text/index-data/tcu-all.html" target="text">standard syntax</a> • <a href="https://w3c.github.io/i18n-drafts/articles/vertical-text/index-data/tcu-all-pref.html" target="text">proprietary syntax</a>

The CSS <code class="kw" translate="no">digits</code> value is only supported by <span class="partial">legacy Edge</span> (with it's proprietary property name), but  single digits are stretched to fit the width of the (vertical) line. The new (Blink-based) Edge no longer supports it. Tests: <a href="https://w3c.github.io/i18n-drafts/articles/vertical-text/index-data/digits.html" target="text">standard syntax</a> • <a href="https://w3c.github.io/i18n-drafts/articles/vertical-text/index-data/digits-pref.html" target="text">proprietary syntax</a>

The unavailability of the <code class="kw" translate="no">digits</code> value is an inconvenience, since more interventions and markup are needed when using the <code class="kw" translate="no">all</code> value.

Please view or discuss this issue at https://github.com/w3c/jlreq/issues/169 using your GitHub account