Instead of sending users away from your Web site when they click on an external link, you can force a new browser window to open. When the size of the new window doesn’t matter, simply select the _blank option in the Target field of the Property Inspector.

This options adds target="_blank" to the link in the source code.

If you want to control the size of the browser window that opens, add the Open Browser Window behavior in the Behaviors panel.

The Open Browser Window dialog will appear:

With this option, you can control the width and height of the window, as well as which toolbars appear in the new window, such as the Navigation Toolbar, the Location toolbar, or Menu Toolbar. You can also control whether scrollbars and resize handles are available to the user.