If you are using Spotipo to enable facebook login on your guest wifi, you might run into the below error.
Can't load URL: The domain of this URL isn't included in the app's domains. To be able to load this URL, add all domains and sub-domains of your app to the App Domains field in your app settings.
This happens when there is mismatch on the URL configured on your facebook app and the URL to which Guests are redirected. Debugging this is quite simple.
Ensure that SSL is enabled
Facebook has mandated that all Apps should be using SSL. If you haven't already, please enable SSL on your Spotipo installation.
Get the full URL when you see this error
If you are getting this error on a mobile device captive network assistant, it's not possible to copy the URL. In such case either connect a laptop to your network or close the captive portal and use a normal browser.
Decode the URL content
Use a decoder like https://www.urldecoder.org/ paste the full URL into the box and press decode.
Inspect the URL content and figure out the Redirect URI
Look into the decoded content, there should be a parameter called redirect_uri
Not down the string after redirect_uri, this should be pointing to your spotipo server.
Check your FB app settings
Login to https://developers.facebook.com and go to your app.
Check under Facebook Login -> Settings, the configured valid Oauth Redirect URI should match the value seen in last step.
Your server name should be configured in app domain as well
Correct the settings on your Device
Check that your router is configured to redirect Guest to the right URL. In case of Unifi controller this will be configured in the index.html