But there's nothing stopping websites from offering that without browser support. It can just show that at the top of the page. Everything it provides is unde

But there's nothing stopping websites from offering that without browser support. It can just show that at the top of the page. Everything it provides is under the authority of the website. The URL needs to be provided by the browser because it's not entirely under the authority of the website, but that's not the case for a breadcrumb bar.