Try webRTC!
This is a project trying out websockets and webRTC, using Next.js and simple-peer.
Run it in development with npm run dev.
Made to work with https://github.com/remyoudemans/signalling-server.
To try it out, run this and the signalling-server locally and go to http:localhost:3000/jeffRoom in two separate browser windows, login in both and move your cursor around and appreciate the cursor sharing!