This issue is applicable to Chinese, Japanese, Korean, and Mongolian.
A common way to orient counters for lists in vertical text is to have an upright number with a dot alongside it.

The expected way to achieve this in HTML would be to use the following CSS: li::marker { text-combine-upright: all; }, however this cannot be used because not all browsers support text-combine-upright applied to counters.
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 not all browsers currently support the CSS Counter Styles specification. So that doesn't work either.
It is a significant nuisance for content authoring to not be able to produce upright counters for lists.
For more details, see this GitHub issue, which is being used to track this gap.
This issue is applicable to Chinese, Japanese, Korean, and Mongolian.
A common way to orient counters for lists in vertical text is to have an upright number with a dot alongside it.
The expected way to achieve this in HTML would be to use the following CSS:
li::marker { text-combine-upright: all; }, however this cannot be used because not all browsers supporttext-combine-uprightapplied to counters.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 not all browsers currently support the CSS Counter Styles specification. So that doesn't work either.
It is a significant nuisance for content authoring to not be able to produce upright counters for lists.
For more details, see this GitHub issue, which is being used to track this gap.