Access to mass mailing features is now limited to users with the proper mass mailing permissions instead of being broadly available to employees. This helps protect mailing lists, campaigns, templates, and reports from unauthorized viewing or use.

Task: https://www.odoo.com/web#id=21666&view_type=form&model=project.task&action=333&active_id=131&menu_id=4720
Pad: https://pad.odoo.com/p/openerp-project.task-ID60ZVLN38