CSS Rhythmic Sizing (css-rhythm-1) is a specification that contains properties that we have not implemented yet. In order to add these properties to the parser, the specification must first be listed as a valid category
<rdar://problem/105458547>
Pull request: https://github.com/WebKit/WebKit/pull/10106
Committed 260280@main (7dbe70207ba5): <https://commits.webkit.org/260280@main> Reviewed commits have been landed. Closing PR #10106 and removing active labels.