Firebase: This domain is not authorized

Question

I imported Firebase JS v3 API and used to initialize Firebase using:

firebase.initializeApp(config);

However the app failed to load correct

Answer 1

Make sure the "authDomain" in your config matches the one in your firebase console. If you're running the app on localhost, make sure it's set to localhost and localhost exists on your firebase console.

Auth -> Sign In Method -> OAuth redirect domains

var config = {
    apiKey: "...",
    authDomain: "...", // this should match the one on your firebase console
    databaseURL: "...",
    storageBucket: "",
};
firebase.initializeApp(config);