diff --git a/src/win32_platform.h b/src/win32_platform.h
index 9a669215..59815146 100644
--- a/src/win32_platform.h
+++ b/src/win32_platform.h
@@ -242,7 +242,9 @@ typedef VkBool32 (APIENTRY *PFN_vkGetPhysicalDeviceWin32PresentationSupportKHR)(
 #include "egl_context.h"
 #include "osmesa_context.h"
 
-#define _GLFW_WNDCLASSNAME L"GLFW30"
+#if !defined(_GLFW_WNDCLASSNAME)
+ #define _GLFW_WNDCLASSNAME L"GLFW30"
+#endif
 
 #define _glfw_dlopen(name) LoadLibraryA(name)
 #define _glfw_dlclose(handle) FreeLibrary((HMODULE) handle)