// Code

<odoo>
<!-- Display internal ref below name -->
<template id="products_internal_reference" inherit_id="website_sale.products_item">
<xpath expr="//div[hasclass('o_wsale_product_information_text')]"
position="after">
<a class="text-primary text-decoration-none" itemprop="name"
t-att-href="product_href"
t-att-content="product.default_code"
t-field="product.default_code" />
</xpath>
</template>
<!-- Display internal ref in product details -->
<template id="products_details_internal_reference"
inherit_id="website_sale.product">
<xpath expr="//div[@id='product_details']//h1"
position="after">
<h4 itemprop="name" t-field="product.default_code"/>
</xpath>
</template>
</odoo>