title: FB.Init() error during gradle build unity
body: <p>I am using Unity 2018.1.6f1 and facebook-unity-sdk-7.13.0. When I try to build the project using gradle, the build is completed successfully but it gives an error while calling FB.Init() </p>
  
  <blockquote>
    <p>"AndroidJavaException: java.lang.ClassNotFoundException:
    com.facebook.unity.FB".</p>
  </blockquote>
  
  <p>I tried the solution in the following links:
  <a href="https://stackoverflow.com/questions/15760581/android-proguard-settings-for-facebook">Android ProGuard settings for Facebook</a></p>
  
  <p>I even checked whether I was using debug keyhash, which I was, but I addded release key hash and still getting the same error.</p>
  
  <p>Any help would be appreciated.</p>
  
  <p>P.S. It works fine in debug build</p>