I'm opening a popup window with plain text I want the user to "save page as" to save the file locally. when the user does do this in IE, it works fine, however, in Firefox it saves the paretn page instead. : this is how I open my window from a button:

that=window.open("blank.html","savein","toolbar=no, location=no, directories=no, status=no, menubar=yes, scrollbars=no, resizable=no, copyhistory=no, width=400, height=400");

that.document.open("text","replace");
that.document.writeln("Your Number is " + UserNum);
that.document.writeln("Your Reference is " + UserRef);
that.document.close();
that.focus();

when the user click on file, save in firefox, it doesnt save the content of the popup, but rather the parent window.