Hi,

The layout used by an email template is controlled by the field 'email_layout_xmlid' on the 'mail.template' model.

To check which layout a template uses:

1. Activate Developer Mode.

2. Go to Settings -> Technical -> Email -> Templates.

3. Open the template and inspect the field 'email_layout_xmlid' via the bug icon.

For templates created manually:

The field is usually empty by default and can pass the layout to the 'email_layout_xmlid' field.

Hello Luc Bernard,
I hope you are doing well

Layout isn't stored on the template. It's chosen by the code that calls send_mail:
1. email_layout_xmlid argument if passed
2. Model default (sale/invoice → mail_notification_layout_with_responsible_signature)
3. Fallback → mail.mail_notification_light

Fix for your own templates: pass email_layout_xmlid='mail.mail_notification_layout' when sending, or inherit that XML view to rebrand globally.

I hope this information helps to you

Thanks & Regards,
Kunjan Patel