note about require.id configurability

src/duk_bi_global.c

@@ -979,8 +979,10 @@ duk_ret_t duk_bi_global_object_require(duk_context *ctx) {
 
 	/* Fresh require: require.id is left configurable (but not writable)
 	 * so that is not easy to accidentally tweak it, but it can still be
-	 * done with Object.defineProperty().  (This could also be just made
-	 * non-configurable, as there is no practical reason to touch it.)
+	 * done with Object.defineProperty().
+	 *
+	 * XXX: require.id could also be just made non-configurable, as there
+	 * is no practical reason to touch it.
 	 */
 	duk_push_c_function(ctx, duk_bi_global_object_require, 1 /*nargs*/);
 	duk_dup(ctx, 3);