diff --git a/dgl/CairoWidget.hpp b/dgl/CairoWidget.hpp
index 1d685444..9ebfe8ff 100644
--- a/dgl/CairoWidget.hpp
+++ b/dgl/CairoWidget.hpp
@@ -102,7 +102,7 @@ private:
         cairoDisplay(fContext);
 
         // get cairo surface data (RGB24)
-        unsigned char* const surfaceData = cairo_image_surface_get_data(fSurface);
+        uchar* const surfaceData = cairo_image_surface_get_data(fSurface);
 
         // enable GL texture
         glEnable(GL_TEXTURE_RECTANGLE_ARB);
diff --git a/dgl/ImageAboutWindow.hpp b/dgl/ImageAboutWindow.hpp
index c812295a..738bc74d 100644
--- a/dgl/ImageAboutWindow.hpp
+++ b/dgl/ImageAboutWindow.hpp
@@ -35,15 +35,15 @@ class ImageAboutWindow : public Window,
                          public Widget
 {
 public:
-    ImageAboutWindow(App& app, Window& parent, const Image& image = Image());
-    ImageAboutWindow(Widget* widget, const Image& image = Image());
+    explicit ImageAboutWindow(Window& parent, const Image& image = Image());
+    explicit ImageAboutWindow(Widget* widget, const Image& image = Image());
 
     void setImage(const Image& image);
 
 protected:
     void onDisplay() override;
     bool onMouse(int button, bool press, int x, int y) override;
-    bool onKeyboard(bool press, uint32_t key) override;
+    bool onKeyboard(bool press, uint key) override;
 
 private:
     Image fImgBackground;
diff --git a/dgl/ImageButton.hpp b/dgl/ImageButton.hpp
index 4d774661..f61c874a 100644
--- a/dgl/ImageButton.hpp
+++ b/dgl/ImageButton.hpp
@@ -35,8 +35,8 @@ public:
     };
 
     ImageButton(Window& parent, const Image& image);
-    ImageButton(Widget* widget, const Image& image);
     ImageButton(Window& parent, const Image& imageNormal, const Image& imageHover, const Image& imageDown);
+    ImageButton(Widget* widget, const Image& image);
     ImageButton(Widget* widget, const Image& imageNormal, const Image& imageHover, const Image& imageDown);
     ImageButton(const ImageButton& imageButton);
 
diff --git a/dgl/StandaloneWindow.hpp b/dgl/StandaloneWindow.hpp
index e5203ee2..c98a0be8 100644
--- a/dgl/StandaloneWindow.hpp
+++ b/dgl/StandaloneWindow.hpp
@@ -57,7 +57,7 @@ public:
         fWindow.setResizable(yesNo);
     }
 
-    void setSize(unsigned int width, unsigned int height)
+    void setSize(uint width, uint height)
     {
         fWindow.setSize(width, height);
     }
diff --git a/dgl/Widget.hpp b/dgl/Widget.hpp
index f0c376f2..b3fec397 100644
--- a/dgl/Widget.hpp
+++ b/dgl/Widget.hpp
@@ -19,12 +19,6 @@
 
 #include "Geometry.hpp"
 
-#ifdef PROPER_CPP11_SUPPORT
-# include <cstdint>
-#else
-# include <stdint.h>
-#endif
-
 START_NAMESPACE_DGL
 
 // -----------------------------------------------------------------------
@@ -35,7 +29,7 @@ class Window;
 class Widget
 {
 public:
-    Widget(Window& parent);
+    explicit Widget(Window& parent);
     virtual ~Widget();
 
     bool isVisible() const noexcept;
@@ -65,17 +59,17 @@ public:
 
     const Rectangle<int>& getArea() const noexcept;
 
-    uint32_t getEventTimestamp();
-    int getModifiers();
+    uint getEventTimestamp();
+    int  getModifiers();
 
-    App& getParentApp() const noexcept;
+    App&    getParentApp() const noexcept;
     Window& getParentWindow() const noexcept;
 
     void repaint();
 
 protected:
     virtual void onDisplay() = 0;
-    virtual bool onKeyboard(bool press, uint32_t key);
+    virtual bool onKeyboard(bool press, uint key);
     virtual bool onMouse(int button, bool press, int x, int y);
     virtual bool onMotion(int x, int y);
     virtual bool onScroll(int x, int y, float dx, float dy);
diff --git a/dgl/Window.hpp b/dgl/Window.hpp
index d78479e5..78c7c36f 100644
--- a/dgl/Window.hpp
+++ b/dgl/Window.hpp
@@ -35,9 +35,9 @@ class Widget;
 class Window
 {
 public:
-    Window(App& app);
-    Window(App& app, Window& parent);
-    Window(App& app, intptr_t parentId);
+    explicit Window(App& app);
+    explicit Window(App& app, Window& parent);
+    explicit Window(App& app, intptr_t parentId);
     virtual ~Window();
 
     void show();
@@ -57,15 +57,15 @@ public:
     int getWidth() const noexcept;
     int getHeight() const noexcept;
     Size<int> getSize() const noexcept;
-    void setSize(unsigned int width, unsigned int height);
+    void setSize(uint width, uint height);
 
     void setTitle(const char* title);
 
     void setTransientWinId(intptr_t winId);
 
-    App&     getApp() const noexcept;
-    uint32_t getEventTimestamp() const;
-    int      getModifiers() const;
+    App& getApp() const noexcept;
+    uint getEventTimestamp() const;
+    int  getModifiers() const;
     intptr_t getWindowId() const;
 
 private:
diff --git a/dgl/src/ImageAboutWindow.cpp b/dgl/src/ImageAboutWindow.cpp
index 67b28860..7065fa28 100644
--- a/dgl/src/ImageAboutWindow.cpp
+++ b/dgl/src/ImageAboutWindow.cpp
@@ -20,13 +20,13 @@ START_NAMESPACE_DGL
 
 // -----------------------------------------------------------------------
 
-ImageAboutWindow::ImageAboutWindow(App& app, Window& parent, const Image& image)
-    : Window(app, parent),
+ImageAboutWindow::ImageAboutWindow(Window& parent, const Image& image)
+    : Window(parent.getApp(), parent),
       Widget((Window&)*this),
       fImgBackground(image)
 {
     Window::setResizable(false);
-    Window::setSize(static_cast<unsigned int>(image.getWidth()), static_cast<unsigned int>(image.getHeight()));
+    Window::setSize(static_cast<uint>(image.getWidth()), static_cast<uint>(image.getHeight()));
     Window::setTitle("About");
 }
 
@@ -36,14 +36,17 @@ ImageAboutWindow::ImageAboutWindow(Widget* widget, const Image& image)
       fImgBackground(image)
 {
     Window::setResizable(false);
-    Window::setSize(static_cast<unsigned int>(image.getWidth()), static_cast<unsigned int>(image.getHeight()));
+    Window::setSize(static_cast<uint>(image.getWidth()), static_cast<uint>(image.getHeight()));
     Window::setTitle("About");
 }
 
 void ImageAboutWindow::setImage(const Image& image)
 {
+    if (fImgBackground == image)
+        return;
+
     fImgBackground = image;
-    Window::setSize(static_cast<unsigned int>(image.getWidth()), static_cast<unsigned int>(image.getHeight()));
+    Window::setSize(static_cast<uint>(image.getWidth()), static_cast<uint>(image.getHeight()));
 }
 
 void ImageAboutWindow::onDisplay()
@@ -62,7 +65,7 @@ bool ImageAboutWindow::onMouse(int, bool press, int, int)
     return false;
 }
 
-bool ImageAboutWindow::onKeyboard(bool press, uint32_t key)
+bool ImageAboutWindow::onKeyboard(bool press, uint key)
 {
     if (press && key == CHAR_ESCAPE)
     {
diff --git a/dgl/src/ImageButton.cpp b/dgl/src/ImageButton.cpp
index 85bb2cc9..c6283466 100644
--- a/dgl/src/ImageButton.cpp
+++ b/dgl/src/ImageButton.cpp
@@ -33,17 +33,6 @@ ImageButton::ImageButton(Window& parent, const Image& image)
 {
 }
 
-ImageButton::ImageButton(Widget* widget, const Image& image)
-    : Widget(widget->getParentWindow()),
-      fImageNormal(image),
-      fImageHover(image),
-      fImageDown(image),
-      fCurImage(&fImageNormal),
-      fCurButton(-1),
-      fCallback(nullptr)
-{
-}
-
 ImageButton::ImageButton(Window& parent, const Image& imageNormal, const Image& imageHover, const Image& imageDown)
     : Widget(parent),
       fImageNormal(imageNormal),
@@ -58,6 +47,17 @@ ImageButton::ImageButton(Window& parent, const Image& imageNormal, const Image&
     setSize(fCurImage->getSize());
 }
 
+ImageButton::ImageButton(Widget* widget, const Image& image)
+    : Widget(widget->getParentWindow()),
+      fImageNormal(image),
+      fImageHover(image),
+      fImageDown(image),
+      fCurImage(&fImageNormal),
+      fCurButton(-1),
+      fCallback(nullptr)
+{
+}
+
 ImageButton::ImageButton(Widget* widget, const Image& imageNormal, const Image& imageHover, const Image& imageDown)
     : Widget(widget->getParentWindow()),
       fImageNormal(imageNormal),
diff --git a/dgl/src/Widget.cpp b/dgl/src/Widget.cpp
index 8e08024d..23e415f1 100644
--- a/dgl/src/Widget.cpp
+++ b/dgl/src/Widget.cpp
@@ -160,7 +160,7 @@ const Rectangle<int>& Widget::getArea() const noexcept
     return fArea;
 }
 
-uint32_t Widget::getEventTimestamp()
+uint Widget::getEventTimestamp()
 {
     return fParent.getEventTimestamp();
 }
@@ -185,7 +185,7 @@ void Widget::repaint()
     fParent.repaint();
 }
 
-bool Widget::onKeyboard(bool, uint32_t)
+bool Widget::onKeyboard(bool, uint)
 {
     return false;
 }
diff --git a/dgl/src/Window.cpp b/dgl/src/Window.cpp
index 20cbf9dc..4c94fb0f 100644
--- a/dgl/src/Window.cpp
+++ b/dgl/src/Window.cpp
@@ -195,7 +195,7 @@ public:
         {
             pid_t pid = getpid();
             Atom _nwp = XInternAtom(xDisplay, "_NET_WM_PID", True);
-            XChangeProperty(xDisplay, xWindow, _nwp, XA_CARDINAL, 32, PropModeReplace, (const unsigned char*)&pid, 1);
+            XChangeProperty(xDisplay, xWindow, _nwp, XA_CARDINAL, 32, PropModeReplace, (const uchar*)&pid, 1);
         }
 #endif
 
@@ -322,7 +322,7 @@ public:
         fVisible = yesNo;
 
         if (yesNo && fFirstInit)
-            setSize(static_cast<unsigned int>(fView->width), static_cast<unsigned int>(fView->height), true);
+            setSize(static_cast<uint>(fView->width), static_cast<uint>(fView->height), true);
 
 #if defined(DISTRHO_OS_WINDOWS)
         if (yesNo)
@@ -378,7 +378,7 @@ public:
 
         fResizable = yesNo;
 
-        setSize(static_cast<unsigned int>(fView->width), static_cast<unsigned int>(fView->height), true);
+        setSize(static_cast<uint>(fView->width), static_cast<uint>(fView->height), true);
     }
 
     // -------------------------------------------------------------------
@@ -398,7 +398,7 @@ public:
         return Size<int>(fView->width, fView->height);
     }
 
-    void setSize(unsigned int width, unsigned int height, const bool forced = false)
+    void setSize(uint width, uint height, const bool forced = false)
     {
         if (width == 0 || height == 0)
         {
@@ -496,7 +496,7 @@ public:
         return puglGetModifiers(fView);
     }
 
-    uint32_t getEventTimestamp() const
+    uint getEventTimestamp() const
     {
         return puglGetEventTimestamp(fView);
     }
@@ -599,7 +599,7 @@ protected:
         }
     }
 
-    void onKeyboard(const bool press, const uint32_t key)
+    void onKeyboard(const bool press, const uint key)
     {
         DBGp("PUGL: onKeyboard : %i %i\n", press, key);
 
@@ -891,7 +891,7 @@ Size<int> Window::getSize() const noexcept
     return pData->getSize();
 }
 
-void Window::setSize(unsigned int width, unsigned int height)
+void Window::setSize(uint width, uint height)
 {
     pData->setSize(width, height);
 }
@@ -916,7 +916,7 @@ int Window::getModifiers() const
     return pData->getModifiers();
 }
 
-uint32_t Window::getEventTimestamp() const
+uint Window::getEventTimestamp() const
 {
     return pData->getEventTimestamp();
 }