PopupButton does not work

Hi,

I am trying to use PopupButton addon from vaadin components https://vaadin.com/directory/component/popupbutton together with clone of quicktickets-dashboard demo https://github.com/vaadin/dashboard-demo but without success. When clicking on the button no popup is shown. The event setPopupVisible is called but nothing is displayed. When I use the same code in other project it works correctly. I wonder if there can be some issue related to EventBus handling which is used in the quicktickets demo.

Thank you for help.

Tomas