My submission for Hack Club's Neon YSWS!
View demo video on YouTube - see it playing Bad Apple
It allows you to stream your screen to the LED matrix via MQTT using a web client (make sure your broker supports WebSockets and you're connecting to it on the correct port from the web app!).
The client is made using Vite + Vanilla TypeScript.
It is deployed on GitHub Pages here.
To run it locally, do:
yarn set version stable # get Yarn v4
cd neon-streamer-client
yarn
yarn dev