Flutter multidex problem With FirebaseAuth , Firestore and Google Sign in

In your app/build.gradle file inside your android folder , add this attribute multiDexEnabled.

         defaultConfig {
                ...
                multiDexEnabled true
            }

Don't forget:

flutter clean

I did for this same error to make it work

multiDexEnabled true

dependencies {
implementation "androidx.multidex:multidex:2.0.1"
}

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