diff --git a/addons/test_mail/tests/test_mail_template_preview.py b/addons/test_mail/tests/test_mail_template_preview.py
index 2442e46a473..213f9e25e43 100644
--- a/addons/test_mail/tests/test_mail_template_preview.py
+++ b/addons/test_mail/tests/test_mail_template_preview.py
@@ -2,11 +2,23 @@
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
 from odoo.addons.test_mail.tests.test_mail_template import TestMailTemplateCommon
-from odoo.tests import tagged
-
+from odoo.tests import tagged, users
+from odoo.tests.common import Form
 
 @tagged('mail_template', 'multi_lang')
 class TestMailTemplateTools(TestMailTemplateCommon):
+    @classmethod
+    def setUpClass(cls):
+        super().setUpClass()
+        cls.test_template_preview = cls.env['mail.template.preview'].create({
+            'mail_template_id': cls.test_template.id,
+        })
+
+    def test_initial_values(self):
+        self.assertTrue(self.test_template.email_to)
+        self.assertTrue(self.test_template.email_cc)
+        self.assertEqual(len(self.test_template.partner_to.split(',')), 2)
+        self.assertTrue(self.test_record.email_from)
 
     def test_mail_template_preview_force_lang(self):
         test_record = self.env['mail.test.lang'].browse(self.test_record.ids)
@@ -24,3 +36,23 @@ class TestMailTemplateTools(TestMailTemplateCommon):
 
         preview.write({'lang': 'en_US'})
         self.assertEqual(preview.body_html, '<p>EnglishBody for %s</p>' % test_record.name)
+
+    @users('employee')
+    def test_mail_template_preview_recipients(self):
+        form = Form(self.test_template_preview)
+        form.resource_ref = self.test_record
+
+        self.assertEqual(form.email_to, self.test_template.email_to)
+        self.assertEqual(form.email_cc, self.test_template.email_cc)
+        self.assertEqual(set(record.id for record in form.partner_ids),
+                         {int(pid) for pid in self.test_template.partner_to.split(',') if pid})
+
+    @users('employee')
+    def test_mail_template_preview_recipients_use_default_to(self):
+        self.test_template.use_default_to = True
+        form = Form(self.test_template_preview)
+        form.resource_ref = self.test_record
+
+        self.assertEqual(form.email_to, self.test_record.email_from)
+        self.assertFalse(form.email_cc)
+        self.assertFalse(form.partner_ids)