diff --git a/.gitignore b/.gitignore
index 0c6f4cb79dd..b8a221c9e52 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 .DS_Store
+/.idea/
 /build/
 /dist/
 /external_binaries/
diff --git a/atom/browser/api/atom_api_window.cc b/atom/browser/api/atom_api_window.cc
index 077dffe0bc5..352b9284cf4 100644
--- a/atom/browser/api/atom_api_window.cc
+++ b/atom/browser/api/atom_api_window.cc
@@ -190,9 +190,21 @@ void Window::OnExecuteWindowsCommand(const std::string& command_name) {
 }
 
 #if defined(OS_WIN)
-void Window::OnWindowMessage(UINT message, WPARAM w_param, uint64_t l_param) {
+v8::Local<v8::Value> Window::ToBuffer(void* val, int size) {
+  auto buffer = node::Buffer::New(isolate(), static_cast<char*>(val), size);
+
+  if (buffer.IsEmpty()) {
+    return v8::Null(isolate());
+  } else {
+    return buffer.ToLocalChecked();
+  }
+}
+
+void Window::OnWindowMessage(UINT message, WPARAM w_param, LPARAM l_param) {
   if (IsWindowMessageHooked(message)) {
-    messages_callback_map_[message].Run(w_param, l_param);
+    messages_callback_map_[message].Run(
+      ToBuffer(static_cast<void*>(&w_param), sizeof(WPARAM)),
+      ToBuffer(static_cast<void*>(&l_param), sizeof(LPARAM)));
   }
 }
 #endif
diff --git a/atom/browser/api/atom_api_window.h b/atom/browser/api/atom_api_window.h
index f4bc4cdba01..ffbd9b63b40 100644
--- a/atom/browser/api/atom_api_window.h
+++ b/atom/browser/api/atom_api_window.h
@@ -77,7 +77,8 @@ class Window : public mate::TrackableObject<Window>,
   void OnExecuteWindowsCommand(const std::string& command_name) override;
 
   #if defined(OS_WIN)
-  void OnWindowMessage(UINT message, WPARAM w_param, uint64_t l_param) override;
+  void OnWindowMessage(UINT message, WPARAM w_param,
+                       LPARAM l_param) override;
   #endif
 
   // mate::Wrappable:
@@ -149,7 +150,10 @@ class Window : public mate::TrackableObject<Window>,
   void SetAspectRatio(double aspect_ratio, mate::Arguments* args);
 
 #if defined(OS_WIN)
-  typedef base::Callback<void(WPARAM, uint64_t)> MessageCallback;
+  v8::Local<v8::Value> ToBuffer(void* val, int size);
+
+  typedef base::Callback<void(v8::Local<v8::Value>,
+                              v8::Local<v8::Value>)> MessageCallback;
   typedef std::map<UINT, MessageCallback> MessageCallbackMap;
   MessageCallbackMap messages_callback_map_;
 
diff --git a/atom/browser/native_window.cc b/atom/browser/native_window.cc
index 6e38f402874..bf400dc8c74 100644
--- a/atom/browser/native_window.cc
+++ b/atom/browser/native_window.cc
@@ -469,7 +469,8 @@ void NativeWindow::NotifyWindowMessage(UINT message, WPARAM w_param,
                                        LPARAM l_param) {
   FOR_EACH_OBSERVER(
       NativeWindowObserver, observers_,
-      OnWindowMessage(message, w_param, static_cast<uint64_t>(l_param)));
+      OnWindowMessage(message, w_param,
+                      l_param));
 }
 #endif
 
diff --git a/atom/browser/native_window_observer.h b/atom/browser/native_window_observer.h
index 240a7277fa0..a76f314129f 100644
--- a/atom/browser/native_window_observer.h
+++ b/atom/browser/native_window_observer.h
@@ -61,7 +61,7 @@ class NativeWindowObserver {
 
   // Called when window message received
   #if defined(OS_WIN)
-  virtual void OnWindowMessage(UINT message, WPARAM wparam, uint64_t lparam) {}
+  virtual void OnWindowMessage(UINT message, WPARAM wparam, LPARAM lparam) {}
   #endif
 
   // Called when renderer is hung.