Duplicate mail in Jira Service Desk when a Jira user is @mention

[Papa]

I have a local Jira Service Desk + Software instance and I need help with a duplicate mail notification. When a Jira user open a issue in Customer Portal and is mentioned in a comment, two diferent mail notification is send, one using the portal template and other with Jira mention template. 

Is there a way to avoid this behavior? I'd like to @mention my users that aren't reporter nor request participant without this additional mail.

[Christian Schneider]

Hi @Papa ,

your issues is already some days old, did you find a solution? I have the very exact same issue with the @mentions-function...