Old notification area (before AppIndicators)

The notification area (systray) was removed from the Unity panel with Ubuntu 11.04, but you could still use it by whitelisting applications which would allow the icons to show up in the notification area. But not any more!

A recent Unity update in Ubuntu 13.04 Raring Ringtail mentions that the "Notification area whitelist is obsolete", so you can no longer get notification area icons by whitelisting applications. However, when the notification area whitelist was introduced, there were many applications that didn't come with AppIndicators so it was a pretty big issue back then, but right now most applications that used to come with a tray icon now use AppIndicators, including popular apps like Dropbox, Steam, Skype (with "sni-qt") and so on. so you can no longer get notification area icons by whitelisting applications. However, when the notification area whitelist was introduced, there were many applications that didn't come with AppIndicators so it was a pretty big issue back then, but right now most applications that used to come with a tray icon now use AppIndicators, including popular apps like Dropbox, Steam, Skype (with "sni-qt") and so on.





Also, all Qt applications tray icons are automatically converted to AppIndicators thanks to the "sni-qt" package.





AppIndicators



