Third and last slice of the E11 keyboard layer (S4c). S4a/S4b covered every card grid and rail; the
table-shaped pages — the channel manager, a playlist, the download center — were still Tab-stop
country: a channel row carries a priority stepper, four action buttons and a tag picker before the next
row's name.
- `ui/DataTable keyboardNav`: the rows are the items, Enter clicks the element a column marks
`data-nav-open`. DataTable renders its rows twice (a table, and a card list below `md`); both register
and `lib/listNav` now walks only lists on screen (`checkVisibility`), so `j` past the last row never
carries on into the hidden copy.
- `lib/listNav` leaves a key something before it already handled (`defaultPrevented`): during a keyboard
drag a playlist row's grip moves the row with the arrows, and dnd-kit takes the key on the document
before listNav's window listener. Without the guard ↓ moved the focus off the grip and dropped the drag.
- `ui/NavGrid as="tbody"` for a table whose body is the list (the playlist, under dnd-kit's
SortableContext).
- Wired: Subscriptions and Discovery tables, the card layout (`ChannelLayoutGrid` → VirtualGrid
`keyboardNav`), Hidden/Blocked cards (the ChannelLink name is a channel's open element); a playlist's
rows (the title plays; the grip keeps Space/Enter); the download queue, library and shared lists (the
play button opens, `IconBtn open`; a row without one opens nothing).
- `listNav.wiring.contract.test`: `VirtualGrid` and `DataTable` must say `keyboardNav` like `Carousel`,
`DownloadRow` is a card; the audit log's table is the one exemption (its rows open nothing), and an
exemption that no longer matches a tag fails the test.
Measured in Chrome: Channels table j → row, ring round the whole row; a row walked down keeps 12px above
the viewport edge, walked up clears the sticky header by 35px; Enter opens the channel. Cards 3 columns:
→ 0→1, ↓ 1→4. Hidden and Discovery: j + Enter open the channel. Playlist: j + Enter plays, Escape returns
focus to the row; a keyboard drag (Enter on the grip, ↓) moves the row with focus kept on the grip, and
Escape cancels with the order unchanged. Downloads library: Enter plays a video row, does nothing on a
plain file row.
Second slice of the E11 keyboard layer (S4b). S4a gave the feed, the library and the channel page
`j`/`k`, the arrows and Enter; Home's shelves and the whole Plex module were still Tab-stop country —
a Plex poster is its own Tab stop, and a rail's cards sat behind every control of the cards before.
- `lib/listNav`: a list that mounts every item no longer declares a count or columns — both are
measured off the DOM when a key is pressed, so an auto-fill grid's columns follow its width and a
rail is one row. ↑ on a list's top row and ↓ on its bottom row go on to the neighbouring list, onto
the item horizontally nearest the one left (owner decision D4: ←→ within a rail, ↑↓ to the rail
above or below). The first `j` skips cards a rail has scrolled out to the left.
- `Carousel keyboardNav` registers the scroller; the scroller gets a 4px inset (against a -4px margin,
layout unchanged) so the focus ring is not clipped, and `[data-nav-index]` a 2.5rem inline scroll
margin so a card stepped into view clears the rail's edge fade and paging arrow.
- `ui/NavGrid`: the plain, fully mounted grid that registers itself.
- `navIndex` on PlexPosterCard / SeasonCard / EpisodeCard (the card root is the item, the poster the
open element — the ring goes round poster and title, D2), PosterTile and Home's ShelfTile (the button
is the item); cast, related and collection-strip buttons carry the attrs directly.
- Wired: Home's comfort and resume rails; Plex Browse titles + episodes, Discover rails + genres,
collection view, playlists/collections browse, person known-for + filmography, show seasons, season
episodes, cast/related strips, info-page cast + collection strips.
- `listNav.wiring.contract.test`: every `Carousel` says `keyboardNav`, every card says `navIndex`, and a
card with `navIndex` sits inside a NavGrid / Carousel / VirtualGrid — both halves are opt-in, and
either one missing leaves a list the keyboard silently skips.
peter