Notifications
Events
Connection opened
Connection failed
Download failed
Upload failed
Transfer complete
Transfer incomplete
Transfer queued
Bonjour
Notification Center
On OS x 10.8 or later, notifications are sent to the Notification Center.
Settings
Notifications can be configured in System Preferences → Notifications.
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The default alert style is Banner which is dismissed automatically after some delay. You can change the type to Alert if you want to have a Close and Show button to dismiss the alert manually.