Append Sub-task Comment to Parent Custom field

[Julian Governale]

Im looking to see if we can append the comment of multiple sub-tasks into a parent custom field?  At the moment im able to set the Custom field value but it overwrites the previous comments  value in this custom field.  

Our use case.

We start with a story and once its transitioned to a specific status we create about 8 sub-tasks for each team that needs to review and approve or reject the change.

When a user add's a comment to the sub-task on the reject or approval screen and the story is in a specific status, we want to copy that last comment to a custom field on the parent to capture the reason for the approval or rejection

I was able to get the automation rule working, but each time a comment is added, it overwrites the previous one.  Is there a way to append the comment to the custom field or will it always overwrite the previous one?  We are on jira cloud, no script runner, we have JMWE but would like to use automation rule if possible.

Current Rule:

[Hana Kučerová · Accepted solution]

Hi @Julian Governale ,

please try to add

{{issue.Feasibility Study Summary}}

before --- to the Feasibility Study Summary field

{{issue.Feasibility Study Summary}}
---
{{triggerIssue.key}}
{{triggerIssue.comments.author.displayName}}
{{triggerIssue.comments.last.body}}

[Julian Governale]

@Hana Kučerová  Thank you so much for the quick response.  that did the trick and its now working as expected!