i am trying to extend a frontend qweb template.

I created this file in my_module/static/src/xml

<?xml version="1.0" encoding="utf-8"?>
<templates>
    <t t-inherit="website_sale_stock.product_availability" t-inherit-mode="extension">
        <xpath expr="//div[@id='out_of_stock_message']" position="inside">
            <p>This is available and ships ... </p>
        </xpath>
    </t>
</templates>

and in my manifest i added

    'assets': {     

        'web.assets_qweb': ['my_module/static/src/xml/*.xml',],

But i get this error:

ValueError: Module website_sale_stock not loaded or inexistent, or templates of addon being loaded (my_module) are misordered - - -


I cant find any documentation about the order in which the templates should be loaded.

The website_sale_stock is in my modules dependencies and is definitely installed.

Any idea what i am doing wrong ?