You submitted https://automerge.org/blog/automerge-2/. But that page has https://automerge.github.io//blog/automerge-2/ as its canonical URL (note the extra slash).* The canonical URL redirected back to automerge.org, still with the double slash. I've fixed the URL now.

* Our software canonizes URLs when it can. I suppose we could make sure the canonical doesn't 404 before doing that, but it's a bit tricky when there's an additional redirect etc.