diff --git a/src/SFML/Window/Unix/GlxContext.cpp b/src/SFML/Window/Unix/GlxContext.cpp
index b16c0e289..fcba14782 100644
--- a/src/SFML/Window/Unix/GlxContext.cpp
+++ b/src/SFML/Window/Unix/GlxContext.cpp
@@ -25,8 +25,8 @@
 ////////////////////////////////////////////////////////////
 // Headers
 ////////////////////////////////////////////////////////////
+#include <SFML/Window/Unix/WindowImplX11.hpp> // important to be included first (conflict with None)
 #include <SFML/Window/Unix/GlxContext.hpp>
-#include <SFML/Window/Unix/WindowImplX11.hpp>
 #include <SFML/Window/Unix/Display.hpp>
 #include <SFML/System/Mutex.hpp>
 #include <SFML/System/Lock.hpp>
diff --git a/src/SFML/Window/Unix/GlxExtensions.hpp b/src/SFML/Window/Unix/GlxExtensions.hpp
index 929e38a7c..8aca2a5b6 100644
--- a/src/SFML/Window/Unix/GlxExtensions.hpp
+++ b/src/SFML/Window/Unix/GlxExtensions.hpp
@@ -25,11 +25,12 @@
 #ifndef SF_POINTER_C_GENERATED_HEADER_GLXWIN_HPP
 #define SF_POINTER_C_GENERATED_HEADER_GLXWIN_HPP
 
-#ifdef __glxext_h_
+#if defined(__glxext_h_) || defined(__glx_glxext_h_)
 #error Attempt to include glx_exts after including glxext.h
 #endif
 
 #define __glxext_h_
+#define __glx_glxext_h_
 
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>