Allow the mail templates to activate the dynamic placeholder like in mass_mailing. task-2978722 closes odoo/odoo#102603 X-original-commit: f98c472a6d3cd79c28b7b91bdc8359c45c4d3c7a Related: odoo/enterprise#32484 Signed-off-by: David Monjoie (dmo) <dmo@odoo.com> Signed-off-by: Geelen Sébastien (sge) <sge@odoo.com>