diff --git a/src/gui/macutils/AppKitImpl.mm b/src/gui/macutils/AppKitImpl.mm
index dec33421e..9bfbc8de7 100644
--- a/src/gui/macutils/AppKitImpl.mm
+++ b/src/gui/macutils/AppKitImpl.mm
@@ -19,6 +19,11 @@
 #import "AppKitImpl.h"
 
 #import <AppKit/NSWorkspace.h>
+#import <Availability.h>
+
+#if __MAC_OS_X_VERSION_MAX_ALLOWED < 101200
+static const NSEventMask NSEventMaskKeyDown = NSKeyDownMask;
+#endif
 
 @implementation AppKitImpl