public void update() {
final BrowserInformationControlInput current = fInfoControl.getInput();
if (current != null && current.getPrevious() != null) {
final BrowserInput previous = current.getPrevious();
setToolTipText(String.format("Go back to %s", previous.getInputName()));
setEnabled(true);
} else {
setToolTipText("");
setEnabled(false);
}