Deleting the comment for attachments added via email orphans the attachments

Issue Summary

If an attachment is added via email and the comment that the attachment was added through is deleted, the attachment remains on the ticket and can be accessed by an agent, however it is no longer accessible to the customer or agent.

Steps to Reproduce

1. Send a reply to a notification email as the reporter or as an agent with an attachment
2. Once the attachment is received and logged on the ticket, delete the comment that added the attachment
3. The attachment remains in the list of attachments, however it is no longer accessible to customers and it cannot be added to a new comment

Expected Results

The primary issue is this behavior is inconsistent. If a user adds an attachment via the Jira Service Management customer portal and an agent deletes the comment, the attachment is deleted.

This so far only is replicable when the attachment is emailed. Therefore either completely remove the attachment associated with the comment or allow for attachments to remain visible / usable to customers. There is a feature request to allow re-attaching these attachments to a public comment:

•  JRACLOUD-72208 - When adding a comment and using the files & images icon doesn't browse the attachments of the issue

Actual Results

The comment is deleted but the attachment remains. Users trying to access these attachments via say links in customer notifications cannot due to a 403 error.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available