You'll notice
Useful3 Signal2
More background notifications now carry a task id, so you get fewer duplicate alerts.
What's wrong with this entry?
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What
Background shell completion, subagent finish, artifact watch lifecycle and observer notifications now attach the task id when queuing a notification. The queue already used that id to avoid notifying the same task twice and to release keepalives, so you should see fewer duplicates.
Evidence
task-notification
Strings lifted out of the shipped bundle, so the claim above can be checked against them.