diff --git a/include/SFML/Graphics/RenderTarget.hpp b/include/SFML/Graphics/RenderTarget.hpp
index 78172431..582ecd57 100644
--- a/include/SFML/Graphics/RenderTarget.hpp
+++ b/include/SFML/Graphics/RenderTarget.hpp
@@ -63,7 +63,7 @@ public :
     /// \param color Fill color to use to clear the render target
     ///
     ////////////////////////////////////////////////////////////
-    void Clear(const Color& color = Color(0, 0, 0));
+    void Clear(const Color& color = Color(0, 0, 0, 255));
 
     ////////////////////////////////////////////////////////////
     /// \brief Draw an object into the target
diff --git a/src/SFML/Window/Linux/GlxContext.cpp b/src/SFML/Window/Linux/GlxContext.cpp
index 28d24d02..44c72412 100644
--- a/src/SFML/Window/Linux/GlxContext.cpp
+++ b/src/SFML/Window/Linux/GlxContext.cpp
@@ -62,7 +62,14 @@ myOwnsWindow(true)
     CreateContext(shared, VideoMode::GetDesktopMode().BitsPerPixel, ContextSettings(0, 0, 0));
 
     // Activate the context
-    SetActive(true);
+    if (shared)
+        SetActive(true);
+
+    // -- Warning --
+    // The "if (shared)" condition fixes this bug:
+    // http://www.sfml-dev.org/forum/viewtopic.php?p=20767#20767
+    // However, it was already there before and removed at revision 1236,
+    // but without any comment... so it might cause other problems in the future
 }
 
 
diff --git a/src/SFML/Window/Win32/WglContext.cpp b/src/SFML/Window/Win32/WglContext.cpp
index 5f2da071..c5164580 100644
--- a/src/SFML/Window/Win32/WglContext.cpp
+++ b/src/SFML/Window/Win32/WglContext.cpp
@@ -59,7 +59,14 @@ myOwnsWindow   (true)
         CreateContext(shared, VideoMode::GetDesktopMode().BitsPerPixel, ContextSettings(0, 0, 0));
 
     // Activate the context
-    SetActive(true);
+    if (shared)
+        SetActive(true);
+
+    // -- Warning --
+    // The "if (shared)" condition fixes this bug:
+    // http://www.sfml-dev.org/forum/viewtopic.php?p=20767#20767
+    // However, it was already there before and removed at revision 1236,
+    // but without any comment... so it might cause other problems in the future
 }