/example/README.md doesn't mention creating an app first

[waded]

I followed example README.md exactly, and result was the example didn't work, with a runtime JS error:

Uncaught TypeError: Cannot read properties of undefined (reading 'sdkConfig')
    at Object.<anonymous> (App.jsx:10:58)

Cause of the above is npm run build produced firebase-config.json that contained an error (with misleading message, firebase/firebase-tools/issues/4007) because I hadn't created a "web" app yet in the Firebase project.

The readme, since it has readers create a new Firebase project, should include a firebase apps:create invocation, to ensure there's a web app available. Could also mention using firebase apps:list, in case the Firebase project is not new, already has 2 apps, which I presume causes the same error(?) - I can imagine people trying to use most of these steps with an existing project.

[Molnfront]

Open your Terminal and be in your example folder and enter firebase use --add. Then you can select any of your firebase projects.

[Molnfront]

But still it will not work. I got the same error:

Uncaught TypeError: Cannot read properties of undefined (reading 'sdkConfig')