Firebase auth: Google sign in pop up window doesn't show up again once after I sign in with an acccount

Google authentication works but the problem is that the sign-in pop up window doesn't show up once after I sign in with an account and sign in with an account automatically. So it doesn't show up when I try to sign in with another account after signing in and logging out. Is this normal behavior? How can I always choose an account when signing in?

Yeah, this is the normal behavior of google auth. Once you sign in with an account, it will automatically use the signed-in account next time as well. If you want to use another account, then you need to clear the app data & cache from the mobile setting. To clear app data & cache, check this one.

I was getting the same problem and this is called a SmartLock which is enabled by default

I am not getting your code but what is did is below

 List<AuthUI.IdpConfig> providers = Arrays.asList(
            new AuthUI.IdpConfig.EmailBuilder().build(),
            new AuthUI.IdpConfig.PhoneBuilder().build(),
            new AuthUI.IdpConfig.GoogleBuilder().build());
    startActivityForResult(AuthUI.getInstance().createSignInIntentBuilder()
            .setAvailableProviders(providers)
            .setIsSmartLockEnabled(false) // just added this line now it asks to sign in at every install 
            .build(), RC_SIGN_IN);

check if you can call this method somewhere

above code gives you a default UI with all the provider which are provided by you

It looks like the framework caches the option you selected from the popup window the first time. To bring popup window be displayed again you need to revoke access from the Google sign-in client:

mGoogleSignInClient.revokeAccess();

See details here: Firebase: How to revoke access to a Google account that is not logged in