title: Firebase invalid api key error in console
body: <p>I use Firebase-auth for my web application I'm developing with electron framework. I created an API key using project settings, and copied it into my html's body as it is suggested in Firebase guide. However, when I open the HTML page on the browser, console shows the following error.</p>
  
  <pre><code>code: "auth/invalid-api-key"
  message: "Your API key is invalid, please check you have copied it correctly."
  __proto__: Error
  </code></pre>
  
  <p>Bottom part of the body of the HTML page is as follows.</p>
  
  <pre><code> &lt;script src="https://www.gstatic.com/firebasejs/5.8.2/firebase.js"&gt;&lt;/script&gt;
            &lt;script&gt;
              // Initialize Firebase
              var config = {
                apiKey: "AIzaSyAXXXXXXXXXXXXXXXXXXXXjILO32ZDxRKY",
                authDomain: "jumbleup-773da.firebaseapp.com",
                databaseURL: "https://jumbleup-773da.firebaseio.com",
                projectId: "jumbleup-773da",
                storageBucket: "jumbleup-773da.appspot.com",
                messagingSenderId: "971123072180"
              };
              firebase.initializeApp(config);
            &lt;/script&gt;
  </code></pre>
  
  <p>Note: I obfuscated the real key by changing 20 digits of it by X.</p>