Today, most of us use very wide screen. When viewing a long document, you have to page down often. You can make emacs display them side by side, such that left bottom continues to right top. Also, when cursor moves to the bottom of left pane, it'll appear on the right top. Here's what to do:
split-window-horizontally. Then, call
You can use mouse to scroll. It'll scroll both panes, but the mouse pointer must be on the pane the cursor is on.
To stop the text flowing behavior, call
follow-mode again to toggle.
Thanks to Zhang Tianjin for mentioning this tip.