Added saving of monitor mode count.
diff --git a/src/internal.h b/src/internal.h
index 1ca3b11..fa27252 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -241,6 +241,7 @@
     int       positionY;
 
     GLFWvidmode*  modes;
+    int           modeCount;
 
     // These are defined in the current port's platform.h
     _GLFW_PLATFORM_MONITOR_STATE;