notifications stay in the tray forever (if not removed manually) in gnome shell

Notifications such as "scheduled backup delayed" and "starting scheduled backup" does not disappear automatically.
I would expect those the "scheduled backup delayed" notification to disappear when the backup starts, and the "starting scheduled backup" notification to disappear when backup finishes (and perhaps add a "backup completed successfully" notification, so I'll know when it's safe to disconnect my backup drive).

I believe GNOME Shell notifications are designed to persistent.

http://blogs.gnome.org/marina/2011/01/07/notifications-with-character/

I am not sure this is a bug

It's not a bug in gnome, it's a bug in Deja Dup. Gnome 3 allows temporary notifications as well.
The best behaviour of these two specific notifications would be:
The backup started should disappear when the backup is complete.
The backup delayed notification should also disappear when the backup started.
An application can control when and if the notifications stop being persistent.

Michael Terry,

Do you want me to file this upstream?

I already did, forgot to add the link here.
https://bugs.launchpad.net/deja-dup/+bug/776483/

Fixed upstream,
http://bazaar.launchpad.net/~deja-dup-team/deja-dup/20/revision/965
http://bazaar.launchpad.net/~deja-dup-team/deja-dup/20/revision/966
http://bazaar.launchpad.net/~deja-dup-team/deja-dup/20/revision/967
http://bazaar.launchpad.net/~deja-dup-team/deja-dup/20/revision/968

CC ME. Waiting for the fix on Fedora...

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