26552 2014-08-11 11:11:57 +0000 [Shadow]: consider supporting :first-child, nth-child() in content select 2014-08-13 02:47:18 +0000 1 1 1 Unclassified WebAppsWG HISTORICAL - Component Model unspecified PC All RESOLVED DUPLICATE 24872 P2 enhancement --- 1 tomalecpub hayato hayato mike public-webapps public-webapps-bugzilla oldest_to_newest 110058 0 tomalecpub 2014-08-11 11:11:57 +0000 "3.6 Satisfying Matching Criteria" Consider following case. Custom Element that extends ordered list(, and creates a pyramid of news) my-article-list shadow root: <div class="lead"> <h1>Breaking news:</h1> <content select=":first-child"></content> </div> <div class="asides"> <content select=":nth-child(2)"></content> <content select=":nth-child(3)"></content> </div> <div> <content></content> </div> And input should look like: <my-article-list> <article>Most important article</article> <article>Important article</article> <article>Important article</article> <article>article</article> ... </my-article-list> Without those pseudo-classes my-articles-list needs to modify light DOM, or at least CSS properties of child nodes, which seems very intrusive to me. Use of ".first", ".second", ... classes also does not seem right. As the user of my-article-list should now be aware how long should he count, and as for ordered list nodes order already serves this information. I know that it was removed via 21924, but unfortunately I have no idea how hard it would be to implement it, and how it could affect performance. I just guess it could be not much worse than `:not()`. 110118 1 hayato 2014-08-13 02:46:37 +0000 Could you re-use bug 24872? Please feel free to re-open bug 24872. *** This bug has been marked as a duplicate of bug 24872 ***