Eexplanation

1 A user logs in.
2 Session is timeout.
3 The user clicks commandButton that has f:ajax tag.
4 The browser requests with Faces-Request:partial/ajax.
5 The server responses 302 with Location header.
6 The browser requests URL that is Location header.
7 The server responses text/xml that do not contain html.
8 The browser do not change screen.