See https://wpt.fyi/results/css/css-counter-styles/counter-style-at-rule/disclosure-styles.html?label=master&label=experimental&aligned&q=css%2Fcss-counter-styles%2Fcounter-style-at-rule%2Fdisclosure-styles.html
<rdar://problem/109014745>
Pull request: https://github.com/WebKit/WebKit/pull/29102
Committed 279404@main (8105a859925c): <https://commits.webkit.org/279404@main> Reviewed commits have been landed. Closing PR #29102 and removing active labels.