Todtler
Look at all the things it doesn't do!
Just you and your writings.
Todtler is a terminal text editor built around a single idea: writing deserves your full and undivided attention. No toolbar, menus, formatting panels, or notifications. Nothing comes between you and the page.
Todtler reads and writes OpenDocument Text (ODT) files, the open standard behind LibreOffice and OpenOffice, so your work will always remain yours, in a format any word processor can open.
with both top- and bottom bars hidden
Todtler is free under a Pay What You Want model. If it helps you write, consider supporting it.