diff --git a/src/MagnumExternal/OpenGL/GL/flextGL.h b/src/MagnumExternal/OpenGL/GL/flextGL.h
index a6752e6d8..78d44e490 100644
--- a/src/MagnumExternal/OpenGL/GL/flextGL.h
+++ b/src/MagnumExternal/OpenGL/GL/flextGL.h
@@ -1,6 +1,10 @@
 #ifndef _flextgl_h_
 #define _flextgl_h_
 
+#include <Corrade/Utility/VisibilityMacros.h>
+
+#include "Magnum/configure.h"
+
 /* Defensive include guards */
 
 #if defined(__glew_h__) || defined(__GLEW_H__)
@@ -36,14 +40,14 @@ void flextGLInit();
 
 /* Function declaration macros */
 
-#ifdef _WIN32
+#ifndef MAGNUM_BUILD_STATIC
     #ifdef FlextGL_EXPORTS
-        #define FLEXTGL_EXPORT __declspec(dllexport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_EXPORT
     #else
-        #define FLEXTGL_EXPORT __declspec(dllimport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_IMPORT
     #endif
 #else
-    #define FLEXTGL_EXPORT __attribute__ ((visibility ("default")))
+    #define FLEXTGL_EXPORT CORRADE_VISIBILITY_STATIC
 #endif
 
 #if defined(_WIN32) && !defined(APIENTRY) && !defined(__CYGWIN__) && !defined(__SCITECH_SNAP__)
diff --git a/src/MagnumExternal/OpenGL/GL/flextGL.h.template b/src/MagnumExternal/OpenGL/GL/flextGL.h.template
index 0876bca4e..e0507a03d 100644
--- a/src/MagnumExternal/OpenGL/GL/flextGL.h.template
+++ b/src/MagnumExternal/OpenGL/GL/flextGL.h.template
@@ -2,6 +2,10 @@
 #ifndef _flextgl_h_
 #define _flextgl_h_
 
+#include <Corrade/Utility/VisibilityMacros.h>
+
+#include "Magnum/configure.h"
+
 /* Defensive include guards */
 
 #if defined(__glew_h__) || defined(__GLEW_H__)
@@ -37,14 +41,14 @@ void flextGLInit();
 
 /* Function declaration macros */
 
-#ifdef _WIN32
+#ifndef MAGNUM_BUILD_STATIC
     #ifdef FlextGL_EXPORTS
-        #define FLEXTGL_EXPORT __declspec(dllexport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_EXPORT
     #else
-        #define FLEXTGL_EXPORT __declspec(dllimport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_IMPORT
     #endif
 #else
-    #define FLEXTGL_EXPORT __attribute__ ((visibility ("default")))
+    #define FLEXTGL_EXPORT CORRADE_VISIBILITY_STATIC
 #endif
 
 #if defined(_WIN32) && !defined(APIENTRY) && !defined(__CYGWIN__) && !defined(__SCITECH_SNAP__)
diff --git a/src/MagnumExternal/OpenGL/GLES2/flextGL.h b/src/MagnumExternal/OpenGL/GLES2/flextGL.h
index 3c7c11b2c..6d7b3ca08 100644
--- a/src/MagnumExternal/OpenGL/GLES2/flextGL.h
+++ b/src/MagnumExternal/OpenGL/GLES2/flextGL.h
@@ -1,6 +1,10 @@
 #ifndef _flextgl_h_
 #define _flextgl_h_
 
+#include <Corrade/Utility/VisibilityMacros.h>
+
+#include "Magnum/configure.h"
+
 /* Defensive include guards */
 
 #if defined(__gl_h_) || defined(__gl2_h_)
@@ -26,14 +30,14 @@ void flextGLInit();
 
 /* Function declaration macros */
 
-#ifdef _WIN32
+#ifndef MAGNUM_BUILD_STATIC
     #ifdef FlextGL_EXPORTS
-        #define FLEXTGL_EXPORT __declspec(dllexport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_EXPORT
     #else
-        #define FLEXTGL_EXPORT __declspec(dllimport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_IMPORT
     #endif
 #else
-    #define FLEXTGL_EXPORT __attribute__ ((visibility ("default")))
+    #define FLEXTGL_EXPORT CORRADE_VISIBILITY_STATIC
 #endif
 
 #if defined(_WIN32) && !defined(APIENTRY) && !defined(__CYGWIN__) && !defined(__SCITECH_SNAP__)
diff --git a/src/MagnumExternal/OpenGL/GLES2/flextGL.h.template b/src/MagnumExternal/OpenGL/GLES2/flextGL.h.template
index c7632591b..c923899c4 100644
--- a/src/MagnumExternal/OpenGL/GLES2/flextGL.h.template
+++ b/src/MagnumExternal/OpenGL/GLES2/flextGL.h.template
@@ -2,6 +2,10 @@
 #ifndef _flextgl_h_
 #define _flextgl_h_
 
+#include <Corrade/Utility/VisibilityMacros.h>
+
+#include "Magnum/configure.h"
+
 /* Defensive include guards */
 
 #if defined(__gl_h_) || defined(__gl2_h_)
@@ -27,14 +31,14 @@ void flextGLInit();
 
 /* Function declaration macros */
 
-#ifdef _WIN32
+#ifndef MAGNUM_BUILD_STATIC
     #ifdef FlextGL_EXPORTS
-        #define FLEXTGL_EXPORT __declspec(dllexport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_EXPORT
     #else
-        #define FLEXTGL_EXPORT __declspec(dllimport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_IMPORT
     #endif
 #else
-    #define FLEXTGL_EXPORT __attribute__ ((visibility ("default")))
+    #define FLEXTGL_EXPORT CORRADE_VISIBILITY_STATIC
 #endif
 
 #if defined(_WIN32) && !defined(APIENTRY) && !defined(__CYGWIN__) && !defined(__SCITECH_SNAP__)
diff --git a/src/MagnumExternal/OpenGL/GLES3/flextGL.h b/src/MagnumExternal/OpenGL/GLES3/flextGL.h
index a14c4a911..7c5b2ed59 100644
--- a/src/MagnumExternal/OpenGL/GLES3/flextGL.h
+++ b/src/MagnumExternal/OpenGL/GLES3/flextGL.h
@@ -1,6 +1,10 @@
 #ifndef _flextgl_h_
 #define _flextgl_h_
 
+#include <Corrade/Utility/VisibilityMacros.h>
+
+#include "Magnum/configure.h"
+
 /* Defensive include guards */
 
 #if defined(__gl_h_) || defined(__gl2_h_) || defined(__gl3_h_) || defined(__gl31_h_)
@@ -30,14 +34,14 @@ void flextGLInit();
 
 /* Function declaration macros */
 
-#ifdef _WIN32
+#ifndef MAGNUM_BUILD_STATIC
     #ifdef FlextGL_EXPORTS
-        #define FLEXTGL_EXPORT __declspec(dllexport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_EXPORT
     #else
-        #define FLEXTGL_EXPORT __declspec(dllimport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_IMPORT
     #endif
 #else
-    #define FLEXTGL_EXPORT __attribute__ ((visibility ("default")))
+    #define FLEXTGL_EXPORT CORRADE_VISIBILITY_STATIC
 #endif
 
 #if defined(_WIN32) && !defined(APIENTRY) && !defined(__CYGWIN__) && !defined(__SCITECH_SNAP__)
diff --git a/src/MagnumExternal/OpenGL/GLES3/flextGL.h.template b/src/MagnumExternal/OpenGL/GLES3/flextGL.h.template
index 42bafb2e8..3c49a3e78 100644
--- a/src/MagnumExternal/OpenGL/GLES3/flextGL.h.template
+++ b/src/MagnumExternal/OpenGL/GLES3/flextGL.h.template
@@ -2,6 +2,10 @@
 #ifndef _flextgl_h_
 #define _flextgl_h_
 
+#include <Corrade/Utility/VisibilityMacros.h>
+
+#include "Magnum/configure.h"
+
 /* Defensive include guards */
 
 #if defined(__gl_h_) || defined(__gl2_h_) || defined(__gl3_h_) || defined(__gl31_h_)
@@ -31,14 +35,14 @@ void flextGLInit();
 
 /* Function declaration macros */
 
-#ifdef _WIN32
+#ifndef MAGNUM_BUILD_STATIC
     #ifdef FlextGL_EXPORTS
-        #define FLEXTGL_EXPORT __declspec(dllexport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_EXPORT
     #else
-        #define FLEXTGL_EXPORT __declspec(dllimport)
+        #define FLEXTGL_EXPORT CORRADE_VISIBILITY_IMPORT
     #endif
 #else
-    #define FLEXTGL_EXPORT __attribute__ ((visibility ("default")))
+    #define FLEXTGL_EXPORT CORRADE_VISIBILITY_STATIC
 #endif
 
 #if defined(_WIN32) && !defined(APIENTRY) && !defined(__CYGWIN__) && !defined(__SCITECH_SNAP__)