WebKit requires whitespace, but the spec doesn't, see: https://github.com/w3c/csswg-drafts/issues/8285
<rdar://problem/104058693>
Pull request: https://github.com/WebKit/WebKit/pull/8430
Committed 258703@main (cd7efe660cf4): <https://commits.webkit.org/258703@main> Reviewed commits have been landed. Closing PR #8430 and removing active labels.