def on_tab_close_clicked(self, event, state_m):
        """Triggered when the states-editor close button is clicked

        Closes the tab.

        :param state_m: The desired state model (the selected state)
        """
        [page, state_identifier] = self.find_page_of_state_m(state_m)
        if page:
            self.close_page(state_identifier, delete=False)