When a user comments or edits a comment in a subtask, that comment will be written to the parent as current user.
This is useful when the assignee of the parent needs to see all comments completed by subtasks without having to go into each one and view the subtasks' comments.
Create a new rule and name it appropriately.
Providing a description will help you to identify what the rule does but this step is optional.
Add a Trigger → Issue Event → Issue Commented
Add the following JQL query:
Update the query and replace the YOURPROJECT with the desired project name.
Issue Component Selector
Add Selector → Issue Selector
Select Parent Issue
Add comment action
Next to the Issue Selector click on Add → Action → Add Comment
Simply use the Select field dropdown to quickly select the Last Comment virtual field. Make sure to select the field from the trigger issue.
Enable the rule by clicking on the Enable button →
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