[iOS] [1.3.1] - MasterDetail closing arbitrarily

is anyone else noticing the Master closing arbitrarily on their MasterDetail page on iOS?

I've got a custom drawer toggler that I inject as an action into various pages to close the drawer. This is the only way that my code closes the drawer. When I put a breakpoint in the IsPresented = false; bit, the breakpoint isn't hit, but the drawer closes on it's own. Has anyone else seen this behavior?

    public enum NavigationDrawerState
    {
        Open,
        Closed
    }

    private Action<NavigationDrawerState> OnToggleRequest()
    {
        return navigationDrawerState =>
        {
            switch (navigationDrawerState)
            {
                case NavigationDrawerState.Open:
                    IsPresented = true;
                    break;
                case NavigationDrawerState.Closed:
                    IsPresented = false;
                    break;
            }
        };
    }