{# The theme ships an empty versions.html and includes it at the end of every page: it is the hole its own hosted flyout drops into, and this fills the same hole with ours. Every class below is the theme's, so the box in the corner, the caret and the panel that expands are positioned, painted and wired by the theme's own stylesheet and script. versions.js only fills in the list. The list cannot be baked in at build time. A version published today would then be missing from the menu of every version built before it - which is exactly the menu somebody reading an old page is looking at. So it is fetched on load from versions.json at the root of the site, which the publishing workflow rewrites on every deployment. data-root is the way back out: pathto('', 1) reaches the root of this build, and one level above that is the root of the site, where the versions live side by side. Hidden until the fetch succeeds, so a local build - which has nothing above it to fetch - shows no menu at all rather than an empty one. #}