Last modified: 2012-08-24 22:18:27 UTC
To reproduce: Go to a blank VisualEditor page, click edit, change entry mode to Heading 1 (or whichever Heading mode), select all (Ctrl-A or Cmd-A), type in some content, press 'Return'. The content will appear (subject to bug 39517), but the 'Return' will cause the cursor to move to the left rather than inserting a newline. Indeed, further 'Returns' will insert newlines only to split a Heading, or when transitioning to a Paragraph or Pre-formatted block.
I just fixed this here: https://gerrit.wikimedia.org/r/#/c/21397/ This fix should release to mediawiki.org on September 3.