diff --git a/overview.js b/overview.js
index ade7fad..75753f0 100644
--- a/overview.js
+++ b/overview.js
@@ -421,7 +421,7 @@ var Overview = class {
         this._oldOverviewReactive = Main.overview._overview.reactive
         Main.overview._overview.reactive = true;
 
-        Utils.hookVfunc(Object.getPrototypeOf(Main.overview._overview), 'button_release_event', () => {
+        Utils.hookVfunc(Object.getPrototypeOf(Main.layoutManager.overviewGroup), 'button_release_event', () => {
             let [x, y] = global.get_pointer();
             let pickedActor = global.stage.get_actor_at_pos(Clutter.PickMode.REACTIVE, x, y);
             
@@ -448,7 +448,7 @@ var Overview = class {
             return;
         
         Main.overview._overview.reactive = this._oldOverviewReactive;
-        Utils.hookVfunc(Object.getPrototypeOf(Main.overview._overview), 'button_release_event', null)
+        Utils.hookVfunc(Object.getPrototypeOf(Main.layoutManager.overviewGroup), 'button_release_event', null)
 
         this._clickToExitEnabled = false;
     }
diff --git a/utils.js b/utils.js
index d78f20c..2ed6e6a 100644
--- a/utils.js
+++ b/utils.js
@@ -276,7 +276,7 @@ var mergeObjects = function(main, bck) {
 var hookVfunc = function(proto, symbol, func) {
     if (!func) return
 
-    if (Gi.gobject_prototype_symbol) {
+    if (Gi.gobject_prototype_symbol && proto[Gi.gobject_prototype_symbol]) {
         proto[Gi.gobject_prototype_symbol][Gi.hook_up_vfunc_symbol] (symbol, func);
     } else {
         proto[Gi.hook_up_vfunc_symbol] (symbol, func);