diff --git a/modules/utils.js b/modules/utils.js
index c9a67591..51bafe5f 100644
--- a/modules/utils.js
+++ b/modules/utils.js
@@ -263,7 +263,7 @@ let TreeStyleTabUtils = {
 		return this.SessionStoreNS.TabRestoreStates;
 	},
 	get SessionStoreNS() {
-		if (!this._SessionStoreNS)
+		if (!this._SessionStoreNS) {
 			try {
 				// resource://app/modules/sessionstore/SessionStore.jsm ?
 				this._SessionStoreNS = Components.utils.import('resource:///modules/sessionstore/SessionStore.jsm', {});