In reply to Tom Bowden.

I just ran a test from a 6,300-word, 22-page Word document on a project I've been working on. Copying from Word and pasting into the block editor worked wonderfully with the basic stuff. Paragraphs, lists, and so on transferred just fine.

What did not transfer one-to-one is highly-custom formatting stuff. The items didn't break. They were just turned into paragraphs. That is actually what I would expect because the block editor would have no knowledge of what that custom formatting should be.

I think it's safe to say that pasting from Word works fine.