I wanted to be able to use a browser tab as a scratchpad. If you host this repo at example.com/notetab/, you can keep that URL open in a browser tab as a scratchpad. It saves to local storage, so anything you type will be saved locally but not remotely.
The important part of this code was slavishly copied from here: https://blog.jverkamp.com/2018/09/26/simple-localstorage-notepad/