<html>
<head>
<script>
var windowURL = '';
var openedWindow;
function openWindow()
{
openedWindow = window.open(windowURL);
}
</script>
</head>
<body>
<button onclick="openWindow()">Open Window</button>
</body>
</html>
<html>
<head>
<script>
var windowURL = '';
var openedWindow;
function openWindow()
{
openedWindow = window.open(windowURL);
}
</script>
</head>
<body>
<button onclick="openWindow()">Open Window</button>
</body>
</html>