diff --git a/src/Magnum/Platform/AbstractXApplication.h b/src/Magnum/Platform/AbstractXApplication.h
index e174ad23c..b86e90796 100644
--- a/src/Magnum/Platform/AbstractXApplication.h
+++ b/src/Magnum/Platform/AbstractXApplication.h
@@ -43,11 +43,7 @@
 #include "Magnum/Math/Vector2.h"
 #include "Magnum/Platform/Platform.h"
 
-namespace Magnum {
-
-class Context;
-
-namespace Platform {
+namespace Magnum { namespace Platform {
 
 namespace Implementation {
     template<class, class, class, class> class AbstractContextHandler;
diff --git a/src/Magnum/Platform/GlutApplication.h b/src/Magnum/Platform/GlutApplication.h
index 4ac8f596b..94dc2e0a7 100644
--- a/src/Magnum/Platform/GlutApplication.h
+++ b/src/Magnum/Platform/GlutApplication.h
@@ -39,11 +39,7 @@
 #include "Magnum/OpenGL.h"
 #include <GL/freeglut.h>
 
-namespace Magnum {
-
-class Context;
-
-namespace Platform {
+namespace Magnum { namespace Platform {
 
 /** @nosubgrouping
 @brief GLUT application
diff --git a/src/Magnum/Platform/Sdl2Application.h b/src/Magnum/Platform/Sdl2Application.h
index 7d6f2597d..2c6c8cef0 100644
--- a/src/Magnum/Platform/Sdl2Application.h
+++ b/src/Magnum/Platform/Sdl2Application.h
@@ -42,11 +42,7 @@
 #include <SDL.h>
 #include <SDL_scancode.h>
 
-namespace Magnum {
-
-class Context;
-
-namespace Platform {
+namespace Magnum { namespace Platform {
 
 /** @nosubgrouping
 @brief SDL2 application