Property jira.permission.comment.denied does not block comments sent by the customer

Issue Summary

Even after adding the property "jira.permission.comment.denied" to a specific status, Jira still allows service desk customers to add comments to the issue by sending an email containing the issue key, in case they are not added as request participants.

Steps to Reproduce

1. In a JSM site, flag the option "Yes, allow all emails that contain a valid issue key to be added as a comment to the issue" under settings > Products > Jira service management > Configuration
2. Create a new issue
3. Add the property jira.permission.comment.denied to any status of the issue's workflow
4. Move the issue to the status where you added the property - Naturally, you will not be able to add comments through the UI
5. Use any email account to add a comment to the issue through email, by mentioning the issue key in the subject and ensuring this account is not added as a request participant in the issue

Expected Results

The comment should not be added and a new issue should be created, as when a request participant tries to comment on the issue.

Actual Results

The comment is added to the issue.

Workaround

You can flag the option "No, do not allow all emails that contain a valid issue key to be added as a comment to the issue" under Products > Jira service management > Configuration, enforcing customers to be added as request participants or in the same organization to properly add comments.