Deep review of the debt burn, each measured in Chrome:
- Back from a sub-view whose focused control the swap removed: the focus keeper put the focus on a
stand-in (the returning list's first item) and `restoreNavPosition`, finding the focus "already
somewhere", gave up — Plex show → Back landed on tile 0, not the tile it was opened from. A
stand-in the keeper placed now counts as untouched, like <body>. The keeper's walk up also stops
at its container: a slot left with nothing focusable no longer sends the focus to the first
control of the whole document.
- DataTable enabled both layouts' keyboard lists with the same flag, and `useListNav` reads its ref
only when the flag changes: after a resize across `md`, the layout that mounted was never
registered (no j/k) and the one that left stayed registered. Each is enabled with its layout.
- A Plex playlist nests blocks and each show's episodes in one DndContext; closestCenter and the
keyboard coordinates weighed every droppable, so a movie landed "over" an episode — announced as
a place in the other list, dropped somewhere else or nowhere. `sameListCollision` and
`sameListKeyboardCoordinates` keep a drag among its siblings; onDragEnd's episode → block
resolution is gone with the case.
- dnd-kit reports the item over itself in the pick-up's own tick; announced, "moved to position 1"
replaced "picked up … use the arrow keys" before a screen reader read it.
dnd-kit's screen-reader text is hard-coded English and names an item by its id ("Draggable item
10357 was dropped", a role of "sortable"). Only the YouTube playlist replaced it; the Plex playlist,
the saved-views list and the side-panel groups read it out under a Hungarian UI — found while
checking the Plex playlist's keyboard reorder on localdev.
`ui/sortableA11y` is now the one place: `useSortableA11y` gives a DndContext its instructions and
announcements (HU/EN, `common.dnd.*`), `useSortableItem` announces the role. The YouTube playlist's
own announcements move onto it, which also fixes them: its lists reorder on drop, so reading the
dragged row's own index said "moved to position 1" at every step and "dropped at position 1"
wherever the row went. The place announced is now the slot the row would land in.
A `local/sortable-a11y` lint rule (with its contract test) refuses a DndContext without
`accessibility` and a direct `useSortable`.
peter