window.showDirectoryPicker opens up a whole new world

I'm also excited about this API. Browsers have always severed the file relationship after data transfer. Keeping a live binding unlocks some neat options.

Viumium is a good example. It has lots of useful options, but it can only be configured via the extension page. Sharing between computers means exporting / importing on every change. With showDirectoryPicker(), I could point it at ~/.config/vimium/options.json and slap some Nix on it.

Excalidraw is another good example. Create a flowchart and it's saved in browser storage. "Export" by copying it to a file. Now come back in a week: is the browser's flowchart accurate, or the one you exported? Export it again, just to be safe. I wish I could just edit the file directly.

My own apps save logs to OPFS. Browsers hide those files. I'd love to have the option to save them somewhere real, philosophically for users to make informed consent about what they share, but more for myself. It would make local development a lot nicer.