--- old/src/java.desktop/macosx/classes/sun/lwawt/macosx/LWCToolkit.java	2019-05-06 14:44:25.049071256 -0700
+++ new/src/java.desktop/macosx/classes/sun/lwawt/macosx/LWCToolkit.java	2019-05-06 14:44:24.913071258 -0700
@@ -190,10 +190,16 @@
     private static final boolean inAWT;
 
     public LWCToolkit() {
-        areExtraMouseButtonsEnabled = Boolean.parseBoolean(System.getProperty("sun.awt.enableExtraMouseButtons", "true"));
-        //set system property if not yet assigned
-        System.setProperty("sun.awt.enableExtraMouseButtons", ""+areExtraMouseButtonsEnabled);
-        initAppkit(ThreadGroupUtils.getRootThreadGroup(), GraphicsEnvironment.isHeadless());
+        final String extraButtons = "sun.awt.enableExtraMouseButtons";
+        AccessController.doPrivileged((PrivilegedAction<Void>) () -> {
+            areExtraMouseButtonsEnabled =
+                 Boolean.parseBoolean(System.getProperty(extraButtons, "true"));
+            //set system property if not yet assigned
+            System.setProperty(extraButtons, ""+areExtraMouseButtonsEnabled);
+            initAppkit(ThreadGroupUtils.getRootThreadGroup(),
+                       GraphicsEnvironment.isHeadless());
+            return null;
+        });
     }
 
     /*