WEB I18N GAP FIXED: Interoperable emphasis marks

Chinese and Japanese have a native way of indicating emphasis for short ranges of inline text which involves placing a small mark above or below the characters being emphasised in horizontal text, and to the right/left in vertical text.

This is now supported, using CSS, in all 3 major browser engines.

Gap report: https://www.w3.org/TR/jpan-gap/#issue173_text_decoration

See CSS Text Decoration for how to use this feature.
https://drafts.csswg.org/css-text-decor/#emphasis-marks