exitOnClose on TabGroup

If I'm reading this commit's comment correctly, using the exitOnClose setting on a tabgroup should work the same as on a window. But using the latest build from git, and having set that option, it seems to have no effect.

Any idea how to get this effect? Not only is going back to the login screen messy, it's also totally broken due to another bug (once a tabgroup is opened, all event listeners on previous windows are destroyed -- ie, once returned to the login screen, the "Log In" button does nothing)

I overcome this issue closing the login ( previous ) window after I open the tabgroup. Take care not to set exitOnClose on the previous window or will break the focus event for tabgroup