If you use "span" alone to reference a grid line it should be considered an invalid declaration (e.g. "grid-column: span;"). https://drafts.csswg.org/css-grid/#typedef-grid-row-start-grid-line This is a port from a Blink patch: https://codereview.chromium.org/1970573004/
Created attachment 278708 [details] Patch
Comment on attachment 278708 [details] Patch Clearing flags on attachment: 278708 Committed r200755: <http://trac.webkit.org/changeset/200755>
All reviewed patches have been landed. Closing bug.