Bulk operations send notifications to customers when "Send mail for this update" is unchecked

Summary

JIRA Service Desk notifications to customers are sent when a bulk operation is performed despite "Send mail for this update" being unchecked.

Steps to Reproduce

1. Create a few issues in a Service Desk Project;
2. Run a simple filter to retrieve these issues;
3. Run a bulk edit operation, to transition these issues and uncheck the "Send mail for this update" box.

Expected Results

No notifications should be sent

Actual Results

On the final move screen a message appears: "Email notifications will NOT be sent for this update."
Notifications are still sent to customers

Workaround

There is no proper workaround for this issue, though there are 2 options available:

1. Shortly disable the outgoing mail server, however this might also impact any other events that require notifications from JIRA.
2. Shortly disable Service Desk notifications. This is less intrusive than option 1 however could still impact notifications on other events than the bulk operation.