Tabbed Modal Page has no Toolbar and ToolbarItems? Bug?

I came across to a strange behavior today. When I push a tabbed page as navigationpage, code below works. I can see the toolbar items and tool bar.
But If I push same page as modal page without any single code, Below code doesnt work, I dont see any toolbar and toolbaritems.
Toolbar items work on a non-tabbed page so what is the deal with that? it is a bug in xamarin forms?

    <TabbedPage.ToolbarItems>
        <ToolbarItem  />
         <ToolbarItem  />
    </TabbedPage.ToolbarItems>