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1.Go to Project Settings → Automation → Create rule
2.Add a Trigger - Incoming Webhook
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3.
Save the webhook URL. It will be needed in the further step.
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4.
Click Add component
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Select Then : Add an Action. From the right table, select Transition issue.
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As Destination status, select Done
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6.
As an actor, select a user that has permission to close an issue.
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7.
Add a webhook step to an approval path definition. In our example, a webhook step will be the last step. In the Request field paste the webhook URL.
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The screen that follows will show like below image.
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