diff --git a/js_src/Printer.js b/js_src/Printer.js
index 5e245c9..dcb79d1 100644
--- a/js_src/Printer.js
+++ b/js_src/Printer.js
@@ -325,6 +325,7 @@ function Printer() {
 	}
 	this.addLeaveWarning = function() {
 		window.onbeforeunload = function() {
+				console.log("WARNING:"+Printer.ON_BEFORE_UNLOAD_MESSAGE);
 				return Printer.ON_BEFORE_UNLOAD_MESSAGE;
 		};
 	}