realm-java: Realm 4.3.1 ClassNotFoundException: Didn't find class "io.realm.internal.async.RealmThreadPoolExecutor"

Goal

Setup realm

Expected Results

Realm configured

Actual Results

12-08 09:26:29.513 8300-8300/com.app E/AndroidRuntime: FATAL EXCEPTION: main
                                                          Process: com.app, PID: 8300
                                                          java.lang.NoClassDefFoundError: Failed resolution of: Lio/realm/internal/async/RealmThreadPoolExecutor;
                                                              at io.realm.BaseRealm.<clinit>(BaseRealm.java:72)
                                                              at io.realm.Realm.init(Realm.java)
                                                              at com.app.controllers.MyApplication.setupRealm(MyApplication.java:142)
                                                              at com.app.controllers.MyApplication.onCreate(MyApplication.java:83)
                                                              at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1032)
                                                              at android.app.ActivityThread.handleBindApplication(ActivityThread.java:5885)
                                                              at android.app.ActivityThread.-wrap3(ActivityThread.java)
                                                              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1703)
                                                              at android.os.Handler.dispatchMessage(Handler.java:102)
                                                              at android.os.Looper.loop(Looper.java:154)
                                                              at android.app.ActivityThread.main(ActivityThread.java:6692)
                                                              at java.lang.reflect.Method.invoke(Native Method)
                                                              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1468)
                                                              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1358)
                                                           Caused by: java.lang.ClassNotFoundException: Didn't find class "io.realm.internal.async.RealmThreadPoolExecutor" on path: DexPathList[[zip file "/data/app/com.app-2/base.apk"],nativeLibraryDirectories=[/data/app/com.app-2/lib/arm64, /data/app/com.app-2/base.apk!/lib/arm64-v8a, /system/lib64, /vendor/lib64]]
                                                              at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
                                                              at java.lang.ClassLoader.loadClass(ClassLoader.java:380)
                                                              at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
                                                              at io.realm.BaseRealm.<clinit>(BaseRealm.java:72) 
                                                              at io.realm.Realm.init(Realm.java) 
                                                              at com.app.controllers.MyApplication.setupRealm(MyApplication.java:142) 
                                                              at com.app.controllers.MyApplication.onCreate(MyApplication.java:83) 
                                                              at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1032) 
                                                              at android.app.ActivityThread.handleBindApplication(ActivityThread.java:5885) 
                                                              at android.app.ActivityThread.-wrap3(ActivityThread.java) 
                                                              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1703) 
                                                              at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                              at android.os.Looper.loop(Looper.java:154) 
                                                              at android.app.ActivityThread.main(ActivityThread.java:6692) 
                                                              at java.lang.reflect.Method.invoke(Native Method) 
                                                              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1468) 
                                                              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1358) 

Steps & Code to Reproduce

Describe your current debugging efforts.

Code Sample

Fails at Realm.init(this);, where this is instance of Application

    private void setupRealm() {
        Realm.init(this);
        try {
            RealmConfiguration newConfig = new RealmConfiguration.Builder().schemaVersion(2).deleteRealmIfMigrationNeeded().compactOnLaunch().build();
            Realm.setDefaultConfiguration(newConfig);
        } catch (RuntimeException ignore) {}
    }

Version of Realm and tooling

Realm version(s): 4.3.1

Which Android version and device: Any