Description

Both the header and sticky header use <header>. This shows up in the a11y tests under the following errors:

Document should not have more than one banner landmark (https://dequeuniversity.com/rules/axe/4.4/landmark-no-duplicate-banner?application=axeAPI)

Ensures landmarks are unique (https://dequeuniversity.com/rules/axe/4.4/landmark-unique?application=axeAPI)

These errors were introduced in https://gerrit.wikimedia.org/r/c/mediawiki/skins/Vector/+/889520, which removed the aria-hidden from the sticky header in order to ensure the TOC remains accessible to screenreader users when the sticky header is present

AC

• The sticky header doesnt use a heading element

Developer notes

This can be fixed by changing the sticky header container to a div, however we also need to update searchToggle which relies on the existance of a header element to initialize the search element. We should a class to be used instead, so cached HTML will need to be considered