https://github.com/mymonero/mymonero-web-js

Building and running locally via npm run start, then accessing the local site with Cog, works.

You can add 'cog http://localhost:9110' to the start command in package.json to auto launch cog when you run npm start run

The mymonero-app-js project would be more ideal but it is an Electron app.

To test without doing anything locally, just run cog https://wallet.mymonero.com