--- a/mobile/android/base/home/PanelManager.java
+++ b/mobile/android/base/home/PanelManager.java
@@ -16,17 +16,16 @@ import org.json.JSONObject;
 
 import android.content.Context;
 import android.content.SharedPreferences;
 import android.preference.PreferenceManager;
 import android.text.TextUtils;
 import android.util.Log;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.atomic.AtomicInteger;
 
 public class PanelManager implements GeckoEventListener {
     private static final String LOGTAG = "GeckoPanelManager";
 
@@ -46,17 +45,17 @@ public class PanelManager implements Gec
 
     public interface RequestCallback {
         public void onComplete(List<PanelInfo> panelInfos);
     }
 
     private static AtomicInteger sRequestId = new AtomicInteger(0);
 
     // Stores set of pending request callbacks.
-    private static final Map<Integer, RequestCallback> sCallbacks = Collections.synchronizedMap(new HashMap<Integer, RequestCallback>());
+    private static final Map<Integer, RequestCallback> sCallbacks = new HashMap<Integer, RequestCallback>();
 
     /**
      * Asynchronously fetches list of available panels from Gecko.
      *
      * @param callback onComplete will be called on the UI thread.
      */
     public void requestAvailablePanels(RequestCallback callback) {
         final int requestId = sRequestId.getAndIncrement();