http://www.natwest.com/common/javascript/library.js - This looks to be the code that's doing it. Here's a snip:
Code:
function popWindow(url,fromFlash) {
this.window.name = "home";
var popupWindow=window.open(url, "_nw", "width="+700+",height="+530+",left=10,top=50,resizable=yes,scrollbars=yes,menubar=yes,location=no,toolbar=yes,status=yes");
if (!IE4down) popupWindow.focus();
BLN_POPUP_CODE_EXECUTED = true; // flag that the popup code has has been executed
if (!fromFlash){
return false;
}
}
function popWindowUnder(url) {
this.window.name = "home";
var popupWindow=window.open(url, "_nw", "width="+653+",height="+376+",left=10,top=50,resizable=yes,scrollbars=yes,menubar=no,location=no,toolbar=no,status=yes");
//if (!IE4down) popupWindow.focus();
parent.window.focus();
BLN_POPUP_CODE_EXECUTED = true; // flag that the popup code has has been executed
}