diff --git a/addons/mass_mailing/static/src/js/mass_mailing_widget.js b/addons/mass_mailing/static/src/js/mass_mailing_widget.js
index acd2c6dacc10ab0ac36d296fcae246e59d75e521..111fde5746c7ad609614b8ae417ebe08a7d725a3 100644
--- a/addons/mass_mailing/static/src/js/mass_mailing_widget.js
+++ b/addons/mass_mailing/static/src/js/mass_mailing_widget.js
@@ -43,6 +43,10 @@ var MassMailingFieldHtml = FieldHtml.extend({
      */
     commitChanges: function () {
         var self = this;
+        if (config.isDebug() && this.mode === 'edit') {
+            var layoutInfo = $.summernote.core.dom.makeLayoutInfo(this.wysiwyg.$editor);
+            $.summernote.pluginEvents.codeview(undefined, undefined, layoutInfo, false);
+        }
         if (this.mode === 'readonly' || !this.isRendered) {
             return this._super();
         }