diff --git a/src/wgl_context.c b/src/wgl_context.c
index 29f8ba887..b28d7255e 100644
--- a/src/wgl_context.c
+++ b/src/wgl_context.c
@@ -202,7 +202,7 @@ static int choosePixelFormat(_GLFWwindow* window,
 
         u->handle = n;
         // always able to create alpha mask on win
-        u->alphaMask = desired->alphaMask;
+        u->alphaMask = 1;
         usableCount++;
     }