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Notification features have been created for users who find convenient and quick solutions the most useful in their work. It is tied directly to your Jira so when something unexpected happens and the SLA timer starts, both the service provider and the customer get informed about all relevant changes. It’s an event-based behavior behaviour and focuses on enhancing and facilitating the process of receiving notifications from Jira.
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Note that the SLA Notification History tab has been added to the view issue screen. It provides information about the Notification's status - verifies whether the message was successfully delivered.