--- a/services/sync/modules/engines/storage-sync.js
+++ b/services/sync/modules/engines/storage-sync.js
@@ -5,16 +5,17 @@
 this.EXPORTED_SYMBOLS = ['StorageSyncEngine'];
 
 var {classes: Cc, interfaces: Ci, utils: Cu} = Components;
 
 Cu.import("resource://services-sync/constants.js");
 Cu.import("resource://services-sync/engines.js");
 Cu.import("resource://services-sync/util.js");
 Cu.import("resource://services-common/async.js");
+Cu.import("resource://gre/modules/ExtensionStorageSync.jsm");
 
 /**
  * The Engine that manages syncing for the web extension "storage"
  * API, and in particular ext.storage.sync.
  *
  * ext.storage.sync is implemented using Kinto, so it has mechanisms
  * for syncing that we do not need to integrate in the Firefox Sync
  * framework, so this is something of a stub.
@@ -27,17 +28,17 @@ StorageSyncEngine.prototype = {
   _trackerObj: StorageSyncTracker,
   // we don't need these since we implement our own sync logic
   _storeObj: undefined,
   _recordObj: undefined,
 
   syncPriority: 10,
 
   _sync: function () {
-    this._log.warn("syncing ext.storage.sync");
+    return ExtensionStorageSync.syncAll();
   },
 };
 
 function StorageSyncTracker(name, engine) {
   Tracker.call(this, name, engine);
   Svc.Obs.add("weave:engine:start-tracking", this);
   Svc.Obs.add("weave:engine:stop-tracking", this);
 }