This is a feature request. Neochat currently shows a badge with a number of notifications when its icon is viewed from the task manager, but since you can exit to tray you cannot see if there are notifications in the tray. I would like to have the OPTION (but not the necessity) of showing notification count in the tray icon as well.
Sorry, we're not interested in implementing this. It would require adding new API to KStatusNotifierItem / QSystemTrayIcon, which would be very hard to achieve and we're not going to fight for it.
Can NeoChat change its icon to a different color, a different icon or some animation when there is an unread notification? Pidgin changes the icon color when there are messages, so it is possible to see that something wants attention. Powerdevil can adjust its icon to indicate the battery charge level, plasma-nm shows the network status etc. I don't see how NeoChat would need changes to the systray API to achieve something similar.