See http://localhost:8080/magnoliaAuthor/demo-project/about/subsection-articles.html

Click on "edit section header", select "left of the text" or "right of the text" as Image Location (who came up with that name btw? It should be "Image Alignment")

Now the result will render the following P in a half-column, see screenshot. I strongly assume the following P should render across the complete main area