diff --git a/js/xpconnect/wrappers/AccessCheck.cpp b/js/xpconnect/wrappers/AccessCheck.cpp
index 91a3a00311b..b157ab78513 100644
--- a/js/xpconnect/wrappers/AccessCheck.cpp
+++ b/js/xpconnect/wrappers/AccessCheck.cpp
@@ -168,7 +168,10 @@ IsPermitted(const char *name, JSFlatString *prop, bool set)
 static bool
 IsFrameId(JSContext *cx, JSObject *obj, jsid id)
 {
-    XPCWrappedNative *wn = XPCWrappedNative::GetWrappedNativeOfJSObject(cx, obj);
+    obj = JS_ObjectToInnerObject(cx, obj);
+    MOZ_ASSERT(!js::IsWrapper(obj));
+    XPCWrappedNative *wn = IS_WN_WRAPPER(obj) ? XPCWrappedNative::Get(obj)
+                                              : nullptr;
     if (!wn) {
         return false;
     }