empty before content should generate a zero width/height line box. div:before { content: ""; display: block; background: red; }
Created attachment 461236 [details] Patch
Created attachment 461237 [details] Patch
Created attachment 461248 [details] Patch
Committed 252872@main (e59fe453982b): <https://commits.webkit.org/252872@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 461248 [details].
<rdar://problem/97675944>