With all the new cases for the TOC added under T306660, the styles for the TOC have gotten even more complex. This is exacerbated by the no-js approach taken in T307900, which reuses and overrides the existing TOC element and it's styles, greatly increasing the chance for regressions across variations in viewport, user selected TOC collapsed state, and sticky header state. Visual regression teset will help us maintain these different cases.
- Add cases for when the collapsed TOC is open in the page title on all viewports (including larger viewports where the "hide" button is clicked first)
- Add cases for when the collapsed TOC is open in the page title with the sidebar open on all viewports
- Add case for when the collapsed TOC is open in the sticky header
- Update tags on relevant cases to include a "collapsed toc" tag for easier searching