I don’t know what the correct language is for this request, but hopefully you understand what I mean. Also I don’t know if there is a technical reason for why this is the way it is.
When we’re writing in the markdown editor, once you reach the end of the visible screen, markdown just continues writing at the bottom of the view pane. It doesn’t given an option to scroll down and move your current writing line to the top of the field. If you’re in a long document (as I am right now, which reminded me to ask about this), it means you’re constantly just writing at the bottom of the viewing pane. Aside from “wasting” the available field of vision, it’s also playing havoc with my neck 
Is there a change that could be done so you can scroll down and move the writing line to the top even when there are no characters below?
The only way to fix it currently is to open the writing pane into a separate window, and then make it smaller so that you can at least position your writing line vaguely where you want it (this isn’t a very nice solution as making the viewing pane smaller then limits what you can see when you’re scrolling through the text, but also I don’t personally like having the editor in a separate window, I prefer to just do it in the main pane). You can also just hit multiple returns until the writing line is where you want it - I’m not keen on this as a solution, it’s messy, but also makes jumping back to where you were writing annoying.