In the default theme + sandbox, when you hover over items in the file browser or tags plugin, there is a left margin between the animation and the main editor. However there is no margin in the Outline plugin. See screenshots. My expectation is that the Outline is styled the same way as the other plugins. (And I believe it was, until sometime recently.) If this is on purpose, e.g., the heading touches the editor to indicate that it will be jumped to, then I just politely comment that it doesn’t look quite right IMO.