The cube view-transition block moves out of pagerite.css into transition
designs (pagerite/themes/{name}/transition.css), handled like banner
designs: served from disk at /_themes/..., injected by the backend as
#pagerite-transition after the banner sheet, and picked site-wide in the
site settings (Data.transition, default cube; GET/PUT /_api/settings
carry transition + the designs found on disk). The site editor swaps the
sheet in place on change; the dev-mode order fixup knows the new id.
Designs: cube (unchanged), crossfade (all navigations), slide (sideways,
both pages moving together) and reveal (clip-path wipe over the
stationary old page) — the latter two mirrored on history-back and
crossfading within a section like cube.
Also compress the site settings form into a two-column grid: site name +
favicon on one row, theme + transition on the next.
LeoVasanko