The Navigator is quite helpful, but unfortunately it seems to close whenever you click on one of the items to navigate to a new page. It is not, however modal, so there doesn’t seem any software structure reason that it should close.
Is there a way to keep it open? This topic came up some time ago, and ostensibly got fixed:
… but in 6.0.7, it closes when clicked… unless there’s a setting somewhere that might keep it open.