diff --git a/Kernel/ProcessGUI.cpp b/Kernel/ProcessGUI.cpp
index 6329bdc876..2fc30ea578 100644
--- a/Kernel/ProcessGUI.cpp
+++ b/Kernel/ProcessGUI.cpp
@@ -7,6 +7,8 @@
 #include <WindowServer/WSWindow.h>
 #include <WindowServer/WSWindowManager.h>
 
+//#define LOG_GUI_SYSCALLS
+
 void Process::initialize_gui_statics()
 {
     Font::initialize();
@@ -104,9 +106,6 @@ int Process::gui$get_window_backing_store(int window_id, GUI_WindowBackingStoreI
 
 int Process::gui$invalidate_window(int window_id, const GUI_Rect* rect)
 {
-#ifdef LOG_GUI_SYSCALLS
-    dbgprintf("%s<%u> gui$invalidate_window (window_id=%d, rect=%p)\n", name().characters(), pid(), window_id, rect);
-#endif
     if (window_id < 0)
         return -EINVAL;
     if (rect && !validate_read_typed(rect))
@@ -114,6 +113,12 @@ int Process::gui$invalidate_window(int window_id, const GUI_Rect* rect)
     auto it = m_windows.find(window_id);
     if (it == m_windows.end())
         return -EBADWINDOW;
+#ifdef LOG_GUI_SYSCALLS
+    if (!rect)
+        dbgprintf("%s<%u> gui$invalidate_window (window_id=%d, rect=(entire))\n", name().characters(), pid(), window_id);
+    else
+        dbgprintf("%s<%u> gui$invalidate_window (window_id=%d, rect={%d,%d %dx%d})\n", name().characters(), pid(), window_id, rect->location.x, rect->location.y, rect->size.width, rect->size.height);
+#endif
     auto& window = *(*it).value;
     auto event = make<WSEvent>(WSEvent::WM_Invalidate);
     if (rect)
diff --git a/LibGUI/GEvent.h b/LibGUI/GEvent.h
index e02aca777c..f697eef8f0 100644
--- a/LibGUI/GEvent.h
+++ b/LibGUI/GEvent.h
@@ -94,9 +94,9 @@ public:
 
 enum class GMouseButton : byte {
     None = 0,
-    Left,
-    Middle,
-    Right,
+    Left = 1,
+    Right = 2,
+    Middle = 4,
 };
 
 enum GKeyboardKey {
diff --git a/LibGUI/GLabel.cpp b/LibGUI/GLabel.cpp
index 8898dab096..d99cdd569c 100644
--- a/LibGUI/GLabel.cpp
+++ b/LibGUI/GLabel.cpp
@@ -18,7 +18,7 @@ void GLabel::set_text(String&& text)
     update();
 }
 
-void GLabel::paint_event(GPaintEvent&)
+void GLabel::paint_event(GPaintEvent& event)
 {
     Painter painter(*this);
     if (fill_with_background_color())
diff --git a/Userland/guitest2.cpp b/Userland/guitest2.cpp
index e9de8788ab..6d5cdb8b71 100644
--- a/Userland/guitest2.cpp
+++ b/Userland/guitest2.cpp
@@ -82,5 +82,9 @@ GWindow* make_launcher_window()
         }
     };
 
+    auto* dummy_button = new GButton(widget);
+    dummy_button->set_relative_rect({ 5, 50, 70, 20 });
+    dummy_button->set_caption("Dummy");
+
     return window;
 }
diff --git a/WindowServer/WSWindowManager.cpp b/WindowServer/WSWindowManager.cpp
index 8260ff2ffb..549d089cbc 100644
--- a/WindowServer/WSWindowManager.cpp
+++ b/WindowServer/WSWindowManager.cpp
@@ -193,9 +193,10 @@ void WSWindowManager::add_window(WSWindow& window)
 void WSWindowManager::move_to_front(WSWindow& window)
 {
     LOCKER(m_lock);
+    if (m_windows_in_order.tail() != &window)
+        invalidate(window);
     m_windows_in_order.remove(&window);
     m_windows_in_order.append(&window);
-    invalidate(window);
 }
 
 void WSWindowManager::remove_window(WSWindow& window)