`<header>` is turned into `<div data-element="head" er="">` on client site, when handling a change of url without refresh of the whole page. https://developer.mozilla.org/en-US/docs/Web/HTML/Element/header
<header>is turned into<div data-element="head" er="">on client site, when handling a change of url without refresh of the whole page.https://developer.mozilla.org/en-US/docs/Web/HTML/Element/header