Why not just use a real text file and edit with a regular notepad/gedit/nano?
The side project ended up being a single-file HTML file I could throw into a browser tab, so I decided to put it up and share on GitHub :)
Related: I read the other day — and only then realized the full absurdity of it — about how if we want to a share a file quickly between two devices in the same room, for most people (non-tech / -devs) the fastest way would go through a server on the other side of the planet.