T289716 introduced a sticky header skeleton. This task aims to ensure compatibility with widely used on-wiki templates that use fixed elements.
Some concerns were raised around the behavior of the sticky header along with other sticky elements on the page (for example sticky table headers on dewiki)
== Acceptance criteria
 Ensure sticky header appears above other sticky page elements for example table elements in https://de.wikipedia.org/wiki/Elvis_Presley/Diskografie without any changes.
 There should be a general solution allowing template editors to add a class to their markup to add compatibility
== Developer notes
Ideally we'd have a general solution and will begin communication with template developers about what they need to change in their templates to guarantee support with the sticky header feature. This should be as simple as adding a class e.g. "mw-sticky-header-element".
Scroll to headers on https://de.wikipedia.org/wiki/Elvis_Presley/Diskografie and ensure that the headers stick to the bottom of the sticky header.