Subject of email notification for 'being mentioned' is incorrect

Previously, when a user is mentioned in a ticket, the mentioned user will receive an email notification with a subject:

Admin mentioned you on TEST-123

But, after the latest release, the subject is changed to:

Admin commented on TEST-123

even though the user is being mentioned in the comment.

Environment

JIRA Cloud

Steps to Reproduce

1. ensure the user is added to the Issue commented notification event in JIRA
2. mention the user in the comment of a ticket
3. the user will receive an email notification

Expected Results

The subject of the email notification:

Admin mentioned you on TEST-123

Actual Results

The subject of the email notification:

Admin commented on TEST-123

Workaround

No workaround at the moment.