No, but you can format documents. (Alt+F)
I have to admit, that I do not really understand, what `Alt+F` does. As far as I can see, this is not the same as a max width like max 40 em, centered in fullscreen mode.
I support this request. Fullscreen mode is not as convenient as WriteMonkey and other "no distraction" text editors.
Please add a Github issue about this.