That post had two paragraphs in the entry box, it's posted as a single block of text.

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This is a second paragraph, separated by a horizontal line.

This is a third paragraph, with an additional blank line.

@RHaseltine - if you are attempting to type HTML I'm stripping it. Just type your comment like you would in MS Word. If you want to insert a horizontal line use the line tool at the top of the editor.