<!-- basic script -->
<script>
 
        var dhxWins = new dhtmlXWindows();
    ...
    var win = dhxWins.createWindow(id, x, y, width, height);
    win.attachURL("windows_content.html");</script>
 
<!-- windows_content.html -->
<input type="button" value="close window" onclick="closeWindow();">
<script>
 
        var dhxWins = new dhtmlXWindows();
    ...
    var win = dhxWins.createWindow(id, x, y, width, height);
    win.attachURL("windows_content.html");</script>