HN Guidelines clearly state:<p><i>Please submit the original source. If a post reports on something found on another site, submit the latter.</i><p><a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;newsguidelines.html" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;newsguidelines.html</a><p>The original source here clearly is the announcement post by Facebook