In https://gerrit.wikimedia.org/r/c/mediawiki/skins/Vector/+/715629/6/includes/templates/skin.mustache#102 regarding the existing placement of the sticky header at the bottom of the page @nray said:
> I'm wondering if accessibility takes a hit if we do this. Consider a user landing on a page, scrolling down to trigger the sticky header and then hitting tab. They might expect to be able to tab through the sticky header first, but now it will be last.
We should review:
* How this feature would work via keyboard (adding tabindex attributes?)
* Should the sticky header be tabbable and what order should it be tabbable?
* Where in the DOM the sticky header is located.
* Whether a sticky header is useful to screen readers, and if not should it be hidden.
# Question to answer
- What level of accessibility should be provided for this feature?
- How should the sticky header behave to screen readers?
- What changes are required to the existing HTML to support this?
# Spike outcome
The decision should be documented in the Vector codebase inside the template via a Mustache template. If this is significant work (more than a move/inline comment) please create a new task capturing the work required.