Add notification bubble in Custom post type Sub Menu or Sub Custom post type
$notification_count = 2; // here we get the count somehow in the code
add_menu_page(
'Tickets',
$notification_count ? sprintf( 'Tickets <span class="awaiting-mod">%d</span>', $notification_count ) : 'Tickets',
'manage_options',
'tickets_page_slug',
'tickets_page_handler'
);