How to hide browser window URL?

Hi,
We want to hide browser URL (location), we are calling below API on ClickHandler
com.google.gwt.user.client.Window.open(“URL”, "",
"menubar=no," +
"location=false," +
"resizable=yes," +
"scrollbars=yes," +
"status=no," +
"dependent=true");

But It's not working. we want this support for all browsers.
Is there any way to achieve this behavior? If there please inform us.

We are using GWT 2.5.1 and smartGWT 3.0