Hi SonnyV

The place were the change on the URL is taking place is on addons/website/models/ir_http.py on the _dispatch method and it happens when you have more than one language enabled for your website and because the controller route for the url have website=True, that will cause to redirect the url with the lang injected. This also will break ajax request since it will not follow that kind of redirects

the route in your case have this notation in the website_sale:

@http.route(['/shop/product/<model("product.template"):product>'], type='http', auth="public", website=True)
def product(self, product, category='', search='', **kwargs):

To disable it just inherit that controller to remove the argument website=True