The "Firebase: Error (Auth/configuration-not-found)" message usually indicates that you have not properly configured your Firebase project for authentication.
To fix this error, make sure that you have followed these steps:
- Go to the Firebase console and create a new project, or select an existing project.
- In the "Authentication" section of the console, click on the "Sign-in Method" tab.
- Enable at least one sign-in method. For example, you can enable the Email/Password sign-in method, or you can enable one of the social media sign-in methods (such as Google or Facebook).
- Follow the instructions in the Firebase documentation to set up the sign-in method you have chosen. This will typically involve configuring your application and adding the necessary Firebase libraries to your project.
Once you have completed these steps, you should be able to use the Firebase authentication system in your application. If you continue to have issues, you may want to check the Firebase documentation or ask for help in the Firebase community forums.