2. An option to hide the editor sidebar on the left side, so that you can move & arrange elements on the webpage as they would appear in the preview. The editor sidebar causes the items to scale to fit on the screen, so they appear differently in the preview. The difference is slight, but it would be better to be able to arrange elements without having to save -> preview several times to get it right.
Good news. We released this with the new Editor UI and the new Topbar!