<odoo>
    <record model="ir.ui.view" id="purchase_order_form_add_comment">
        <field name="name">comment_template.purchase.order.form</field>
        <field name="model">purchase.order</field>
        <field name="inherit_id" ref="purchase.purchase_order_form" />
        <field name="arch" type="xml">
            <xpath expr="//notebook" position="inside">
                <page string="Comments" name="comments">
                    <field
                        name="comment_template_ids"
                        context="{'default_models': 'purchase.order'}"
                    />
                </page>
            </xpath>
        </field>
    </record>
</odoo>
