doesn't check for visibility before centering

runModalSession

- (void)runModalSession:(CPModalSession)aModalSession
{
    aModalSession._previous = _currentSession;
    _currentSession = aModalSession;

    var theWindow = aModalSession._window;

    [theWindow center];
    [theWindow makeKeyWindow];
    [theWindow orderFront:self];

//    [theWindow._bridge _obscureWindowsBelowModalWindow];

    [CPApp setCallback:_CPRunModalLoop forNextEventMatchingMask:CPAnyEventMask untilDate:nil inMode:0 dequeue:NO];
}