diff --git a/ReactAndroid/src/main/java/com/facebook/react/ReactInstanceManagerImpl.java b/ReactAndroid/src/main/java/com/facebook/react/ReactInstanceManagerImpl.java
index 0baef21f2..780cdb123 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/ReactInstanceManagerImpl.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/ReactInstanceManagerImpl.java
@@ -108,8 +108,8 @@ import com.facebook.systrace.Systrace;
       new ReactInstanceDevCommandsHandler() {
 
         @Override
-        public void onReloadWithJSDebugger(JavaJSExecutor jsExecutor) {
-          ReactInstanceManagerImpl.this.onReloadWithJSDebugger(jsExecutor);
+        public void onReloadWithJSDebugger(JavaJSExecutor.Factory jsExecutorFactory) {
+          ReactInstanceManagerImpl.this.onReloadWithJSDebugger(jsExecutorFactory);
         }
 
         @Override
@@ -132,18 +132,18 @@ import com.facebook.systrace.Systrace;
       };
 
   private class ReactContextInitParams {
-    private final JavaScriptExecutor mJsExecutor;
+    private final JavaScriptExecutor.Factory mJsExecutorFactory;
     private final JSBundleLoader mJsBundleLoader;
 
     public ReactContextInitParams(
-        JavaScriptExecutor jsExecutor,
+        JavaScriptExecutor.Factory jsExecutorFactory,
         JSBundleLoader jsBundleLoader) {
-      mJsExecutor = Assertions.assertNotNull(jsExecutor);
+      mJsExecutorFactory = Assertions.assertNotNull(jsExecutorFactory);
       mJsBundleLoader = Assertions.assertNotNull(jsBundleLoader);
     }
 
-    public JavaScriptExecutor getJsExecutor() {
-      return mJsExecutor;
+    public JavaScriptExecutor.Factory getJsExecutorFactory() {
+      return mJsExecutorFactory;
     }
 
     public JSBundleLoader getJsBundleLoader() {
@@ -156,8 +156,7 @@ import com.facebook.systrace.Systrace;
    * be executing one at time, see {@link #recreateReactContextInBackground()}.
    */
   private final class ReactContextInitAsyncTask extends
-      AsyncTask<ReactContextInitParams, Void, ReactApplicationContext> {
-
+      AsyncTask<ReactContextInitParams, Void, Result<ReactApplicationContext>> {
     @Override
     protected void onPreExecute() {
       if (mCurrentReactContext != null) {
@@ -167,15 +166,23 @@ import com.facebook.systrace.Systrace;
     }
 
     @Override
-    protected ReactApplicationContext doInBackground(ReactContextInitParams... params) {
+    protected Result<ReactApplicationContext> doInBackground(ReactContextInitParams... params) {
       Assertions.assertCondition(params != null && params.length > 0 && params[0] != null);
-      return createReactContext(params[0].getJsExecutor(), params[0].getJsBundleLoader());
+      try {
+        JavaScriptExecutor jsExecutor = params[0].getJsExecutorFactory().create();
+        return Result.of(createReactContext(jsExecutor, params[0].getJsBundleLoader()));
+      } catch (Exception e) {
+        // Pass exception to onPostExecute() so it can be handled on the main thread
+        return Result.of(e);
+      }
     }
 
     @Override
-    protected void onPostExecute(ReactApplicationContext reactContext) {
+    protected void onPostExecute(Result<ReactApplicationContext> result) {
       try {
-        setupReactContext(reactContext);
+        setupReactContext(result.get());
+      } catch (Exception e) {
+        mDevSupportManager.handleException(e);
       } finally {
         mIsContextInitAsyncTaskRunning = false;
       }
@@ -183,13 +190,46 @@ import com.facebook.systrace.Systrace;
       // Handle enqueued request to re-initialize react context.
       if (mPendingReactContextInitParams != null) {
         recreateReactContextInBackground(
-            mPendingReactContextInitParams.getJsExecutor(),
+            mPendingReactContextInitParams.getJsExecutorFactory(),
             mPendingReactContextInitParams.getJsBundleLoader());
         mPendingReactContextInitParams = null;
       }
     }
   }
 
+  private static class Result<T> {
+    @Nullable private final T mResult;
+    @Nullable private final Exception mException;
+
+    public static <T, U extends T> Result<T> of(U result) {
+      return new Result<T>(result);
+    }
+
+    public static <T> Result<T> of(Exception exception) {
+      return new Result<>(exception);
+    }
+
+    private Result(T result) {
+      mException = null;
+      mResult = result;
+    }
+
+    private Result(Exception exception) {
+      mException = exception;
+      mResult = null;
+    }
+
+    public T get() throws Exception {
+      if (mException != null) {
+        throw mException;
+      }
+
+      Assertions.assertNotNull(mResult);
+
+      return mResult;
+    }
+  }
+
   /* package */ ReactInstanceManagerImpl(
       Context applicationContext,
       @Nullable String jsBundleFile,
@@ -311,7 +351,7 @@ import com.facebook.systrace.Systrace;
 
   private void recreateReactContextInBackgroundFromBundleFile() {
     recreateReactContextInBackground(
-        new JSCJavaScriptExecutor(),
+        new JSCJavaScriptExecutor.Factory(),
         JSBundleLoader.createFileLoader(mApplicationContext, mJSBundleFile));
   }
 
@@ -504,9 +544,9 @@ import com.facebook.systrace.Systrace;
     return mCurrentReactContext;
   }
 
-  private void onReloadWithJSDebugger(JavaJSExecutor jsExecutor) {
+  private void onReloadWithJSDebugger(JavaJSExecutor.Factory jsExecutorFactory) {
     recreateReactContextInBackground(
-        new ProxyJavaScriptExecutor(jsExecutor),
+        new ProxyJavaScriptExecutor.Factory(jsExecutorFactory),
         JSBundleLoader.createRemoteDebuggerBundleLoader(
             mDevSupportManager.getJSBundleURLForRemoteDebugging(),
             mDevSupportManager.getSourceUrl()));
@@ -514,18 +554,19 @@ import com.facebook.systrace.Systrace;
 
   private void onJSBundleLoadedFromServer() {
     recreateReactContextInBackground(
-        new JSCJavaScriptExecutor(),
+        new JSCJavaScriptExecutor.Factory(),
         JSBundleLoader.createCachedBundleFromNetworkLoader(
             mDevSupportManager.getSourceUrl(),
             mDevSupportManager.getDownloadedJSBundleFile()));
   }
 
   private void recreateReactContextInBackground(
-      JavaScriptExecutor jsExecutor,
+      JavaScriptExecutor.Factory jsExecutorFactory,
       JSBundleLoader jsBundleLoader) {
     UiThreadUtil.assertOnUiThread();
 
-    ReactContextInitParams initParams = new ReactContextInitParams(jsExecutor, jsBundleLoader);
+    ReactContextInitParams initParams =
+        new ReactContextInitParams(jsExecutorFactory, jsBundleLoader);
     if (!mIsContextInitAsyncTaskRunning) {
       // No background task to create react context is currently running, create and execute one.
       ReactContextInitAsyncTask initTask = new ReactContextInitAsyncTask();
diff --git a/ReactAndroid/src/main/java/com/facebook/react/bridge/JSCJavaScriptExecutor.java b/ReactAndroid/src/main/java/com/facebook/react/bridge/JSCJavaScriptExecutor.java
index d371cf5be..32b261930 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/bridge/JSCJavaScriptExecutor.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/bridge/JSCJavaScriptExecutor.java
@@ -14,6 +14,12 @@ import com.facebook.soloader.SoLoader;
 
 @DoNotStrip
 public class JSCJavaScriptExecutor extends JavaScriptExecutor {
+  public static class Factory implements JavaScriptExecutor.Factory {
+    @Override
+    public JavaScriptExecutor create() throws Exception {
+      return new JSCJavaScriptExecutor();
+    }
+  }
 
   static {
     SoLoader.loadLibrary(ReactBridge.REACT_NATIVE_LIB);
diff --git a/ReactAndroid/src/main/java/com/facebook/react/bridge/JavaJSExecutor.java b/ReactAndroid/src/main/java/com/facebook/react/bridge/JavaJSExecutor.java
index 3c8eb4574..5c1b01b22 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/bridge/JavaJSExecutor.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/bridge/JavaJSExecutor.java
@@ -18,7 +18,11 @@ import com.facebook.proguard.annotations.DoNotStrip;
  */
 @DoNotStrip
 public interface JavaJSExecutor {
-  public static class ProxyExecutorException extends Exception {
+  interface Factory {
+    JavaJSExecutor create() throws Exception;
+  }
+
+  class ProxyExecutorException extends Exception {
     public ProxyExecutorException(Throwable cause) {
       super(cause);
     }
diff --git a/ReactAndroid/src/main/java/com/facebook/react/bridge/JavaScriptExecutor.java b/ReactAndroid/src/main/java/com/facebook/react/bridge/JavaScriptExecutor.java
index 2bc5e26c5..bdf7e4fc6 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/bridge/JavaScriptExecutor.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/bridge/JavaScriptExecutor.java
@@ -14,6 +14,9 @@ import com.facebook.proguard.annotations.DoNotStrip;
 
 @DoNotStrip
 public abstract class JavaScriptExecutor extends Countable {
+  public interface Factory {
+    JavaScriptExecutor create() throws Exception;
+  }
 
   /**
    * Close this executor and cleanup any resources that it was using. No further calls are
diff --git a/ReactAndroid/src/main/java/com/facebook/react/bridge/ProxyJavaScriptExecutor.java b/ReactAndroid/src/main/java/com/facebook/react/bridge/ProxyJavaScriptExecutor.java
index f9e58869b..80cd6f4b3 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/bridge/ProxyJavaScriptExecutor.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/bridge/ProxyJavaScriptExecutor.java
@@ -24,6 +24,18 @@ import com.facebook.proguard.annotations.DoNotStrip;
  */
 @DoNotStrip
 public class ProxyJavaScriptExecutor extends JavaScriptExecutor {
+  public static class Factory implements JavaScriptExecutor.Factory {
+    private final JavaJSExecutor.Factory mJavaJSExecutorFactory;
+
+    public Factory(JavaJSExecutor.Factory javaJSExecutorFactory) {
+      mJavaJSExecutorFactory = javaJSExecutorFactory;
+    }
+
+    @Override
+    public JavaScriptExecutor create() throws Exception {
+      return new ProxyJavaScriptExecutor(mJavaJSExecutorFactory.create());
+    }
+  }
 
   static {
     SoLoader.loadLibrary(ReactBridge.REACT_NATIVE_LIB);
diff --git a/ReactAndroid/src/main/java/com/facebook/react/bridge/WebsocketJavaScriptExecutor.java b/ReactAndroid/src/main/java/com/facebook/react/bridge/WebsocketJavaScriptExecutor.java
index 0fba2b0a3..cddadba00 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/bridge/WebsocketJavaScriptExecutor.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/bridge/WebsocketJavaScriptExecutor.java
@@ -13,10 +13,10 @@ import javax.annotation.Nullable;
 
 import java.util.HashMap;
 import java.util.concurrent.Semaphore;
-import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import android.os.Handler;
+import android.os.Looper;
 
 import com.facebook.infer.annotation.Assertions;
 
@@ -97,9 +97,13 @@ public class WebsocketJavaScriptExecutor implements JavaJSExecutor {
       String webSocketServerUrl,
       final JSExecutorConnectCallback callback) {
     final JSDebuggerWebSocketClient client = new JSDebuggerWebSocketClient();
-    final Handler timeoutHandler = new Handler();
+    final Handler timeoutHandler = new Handler(Looper.getMainLooper());
     client.connect(
         webSocketServerUrl, new JSDebuggerWebSocketClient.JSDebuggerCallback() {
+          // It's possible that both callbacks can fire on an error so make sure we only
+          // dispatch results once to our callback.
+          private boolean didSendResult = false;
+
           @Override
           public void onSuccess(@Nullable String response) {
             client.prepareJSRuntime(
@@ -108,20 +112,30 @@ public class WebsocketJavaScriptExecutor implements JavaJSExecutor {
                   public void onSuccess(@Nullable String response) {
                     timeoutHandler.removeCallbacksAndMessages(null);
                     mWebSocketClient = client;
-                    callback.onSuccess();
+                    if (!didSendResult) {
+                      callback.onSuccess();
+                      didSendResult = true;
+                    }
                   }
 
                   @Override
                   public void onFailure(Throwable cause) {
                     timeoutHandler.removeCallbacksAndMessages(null);
-                    callback.onFailure(cause);
+                    if (!didSendResult) {
+                      callback.onFailure(cause);
+                      didSendResult = true;
+                    }
                   }
                 });
           }
 
           @Override
           public void onFailure(Throwable cause) {
-            callback.onFailure(cause);
+            timeoutHandler.removeCallbacksAndMessages(null);
+            if (!didSendResult) {
+              callback.onFailure(cause);
+              didSendResult = true;
+            }
           }
         });
     timeoutHandler.postDelayed(
diff --git a/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevSupportManager.java b/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevSupportManager.java
index bcc094062..ce60e861c 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevSupportManager.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevSupportManager.java
@@ -15,6 +15,9 @@ import java.io.File;
 import java.io.IOException;
 import java.util.LinkedHashMap;
 import java.util.Locale;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
 
 import android.app.AlertDialog;
 import android.app.ProgressDialog;
@@ -35,14 +38,15 @@ import com.facebook.common.logging.FLog;
 import com.facebook.infer.annotation.Assertions;
 import com.facebook.react.R;
 import com.facebook.react.bridge.CatalystInstance;
+import com.facebook.react.bridge.JavaJSExecutor;
 import com.facebook.react.bridge.NativeModuleCallExceptionHandler;
-import com.facebook.react.bridge.ProxyJavaScriptExecutor;
 import com.facebook.react.bridge.ReactContext;
 import com.facebook.react.bridge.ReadableArray;
 import com.facebook.react.bridge.UiThreadUtil;
 import com.facebook.react.bridge.WebsocketJavaScriptExecutor;
 import com.facebook.react.common.ReactConstants;
 import com.facebook.react.common.ShakeDetector;
+import com.facebook.react.common.futures.SimpleSettableFuture;
 import com.facebook.react.devsupport.StackTraceHelper.StackFrame;
 import com.facebook.react.modules.debug.DeveloperSettings;
 
@@ -534,38 +538,47 @@ public class DevSupportManager implements NativeModuleCallExceptionHandler {
     // anyway
     mDevServerHelper.launchChromeDevtools();
 
-    final WebsocketJavaScriptExecutor webSocketJSExecutor = new WebsocketJavaScriptExecutor();
-    webSocketJSExecutor.connect(
-        mDevServerHelper.getWebsocketProxyURL(),
-        new WebsocketJavaScriptExecutor.JSExecutorConnectCallback() {
-          @Override
-          public void onSuccess() {
-            progressDialog.dismiss();
-            UiThreadUtil.runOnUiThread(
-                new Runnable() {
-                  @Override
-                  public void run() {
-                    mReactInstanceCommandsHandler.onReloadWithJSDebugger(
-                        webSocketJSExecutor);
-                  }
-                });
-          }
+    JavaJSExecutor.Factory factory = new JavaJSExecutor.Factory() {
+      @Override
+      public JavaJSExecutor create() throws Exception {
+        WebsocketJavaScriptExecutor executor = new WebsocketJavaScriptExecutor();
+        SimpleSettableFuture<Boolean> future = new SimpleSettableFuture<>();
+        executor.connect(
+            mDevServerHelper.getWebsocketProxyURL(),
+            getExecutorConnectCallback(progressDialog, future));
+        // TODO(t9349129) Don't use timeout
+        try {
+          future.get(90, TimeUnit.SECONDS);
+          return executor;
+        } catch (ExecutionException e) {
+          throw (Exception) e.getCause();
+        } catch (InterruptedException | TimeoutException e) {
+          throw new RuntimeException(e);
+        }
+      }
+    };
+    mReactInstanceCommandsHandler.onReloadWithJSDebugger(factory);
+  }
 
-          @Override
-          public void onFailure(final Throwable cause) {
-            progressDialog.dismiss();
-            FLog.e(ReactConstants.TAG, "Unable to connect to remote debugger", cause);
-            UiThreadUtil.runOnUiThread(
-                new Runnable() {
-                  @Override
-                  public void run() {
-                    showNewJavaError(
-                        mApplicationContext.getString(R.string.catalyst_remotedbg_error),
-                        cause);
-                  }
-                });
-          }
-        });
+  private WebsocketJavaScriptExecutor.JSExecutorConnectCallback getExecutorConnectCallback(
+      final ProgressDialog progressDialog,
+      final SimpleSettableFuture<Boolean> future) {
+    return new WebsocketJavaScriptExecutor.JSExecutorConnectCallback() {
+      @Override
+      public void onSuccess() {
+        future.set(true);
+        progressDialog.dismiss();
+      }
+
+      @Override
+      public void onFailure(final Throwable cause) {
+        progressDialog.dismiss();
+        FLog.e(ReactConstants.TAG, "Unable to connect to remote debugger", cause);
+        future.setException(
+            new IOException(
+                mApplicationContext.getString(R.string.catalyst_remotedbg_error), cause));
+      }
+    };
   }
 
   private void reloadJSFromServer(final ProgressDialog progressDialog) {
diff --git a/ReactAndroid/src/main/java/com/facebook/react/devsupport/ReactInstanceDevCommandsHandler.java b/ReactAndroid/src/main/java/com/facebook/react/devsupport/ReactInstanceDevCommandsHandler.java
index e97b16f7d..ce3639be8 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/devsupport/ReactInstanceDevCommandsHandler.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/devsupport/ReactInstanceDevCommandsHandler.java
@@ -20,7 +20,7 @@ public interface ReactInstanceDevCommandsHandler {
   /**
    * Request react instance recreation with JS debugging enabled.
    */
-  void onReloadWithJSDebugger(JavaJSExecutor proxyExecutor);
+  void onReloadWithJSDebugger(JavaJSExecutor.Factory proxyExecutorFactory);
 
   /**
    * Notify react instance manager about new JS bundle version downloaded from the server.