So this is a nice solution for the preview mode; I can choose the max-width of the text, and the scroll bar is on the far right. However, now, in source view I have two scroll bars which is pretty ugly. Is there any way for edit mode to have this same feature (user specified width, scroll bar on the far right)?
.CodeMirror-scroll, .markdown-preview-section {
max-width: 40rem;
margin: auto;
}