EDIT: To check if user is ‘made-up’ or ‘real’, just send an email verification by calling FirebaseAuth. instance. currentUser. sendEmailVerification() and ask user to click the link sent in their email , if user is able to perform this action then email exists otherwise it’s ‘made-up’.
Read moreHow do you get current logged in on Flutter?
In the following steps, you will be able to build app a get current user.
Read moreHow do you get a user email in Flutter Firebase?
Follow the steps to Firebase email and password authentication in the Flutter application.
Read moreHow does authentication work in Flutter?
Upon completion of the sign-in transaction, the users authenticate with the authorization server and return to the application . Inside the AuthorizationTokenResponse result object, you receive three tokens: accessToken : an OAuth 2.0 artifact that allows the application to call secure APIs on behalf of the user.
Read moreHow do I use Firebase authentication?
Get Started with Firebase Authentication on Websites
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