screentinker/docs/player-parity.md

# Player parity matrix

What each player can actually do, verified against the code rather than assumed. This is the
document that says where the remaining work is, so a wrong "yes" here is worse than a missing row:
it puts a control on the dashboard that cannot work.

Capability names come from `server/lib/player-capabilities.js`. Players declare their own set at
registration; a player that declares nothing falls back to the per-platform baseline in that file.

**Legend** — ✅ verified in source · ⚠️ partial/conditional (reason given) · ❌ not supported (reason
given) · 💀 **dead**: the capability is declared or baselined but the control cannot work · ❓
**unverifiable from source** — needs hardware, and is marked as such rather than asserted.

BrightSign runs the *same* `server/player/index.html` as the browser, so it differs only where the
`autorun.brs` host bridge adds something the browser cannot reach. The bridge has two halves: the
JS (`brightsign/st-bridge.js`, served by us at `/player/st-bridge.js`, always current) and the
on-device BrightScript that must create the widget with `nodejs_enabled:true`. `BS.hasHost()` is
false unless BOTH are present, and everything host-backed hangs off it.

Verified at `2237eda`. Where a row cites "the fielded build" it means `v1.9.28` — the last release
before any player declared anything, and therefore the build every baseline is describing.

---

## 🔴 Read this first: three dead controls found by this audit

These are not gaps in coverage. They are controls a customer can press today that do nothing.

### 1. The volume slider works on Android only

`frontend/js/views/device-detail.js` sends `set_volume` as **`{ level: 0..1 }`**:

```js
el?.addEventListener('change', () => sendCommand(device.id, cmd, { level: parseInt(el.value, 10) / 100 }));
```

| player | what the handler reads | result |
|---|---|---|
| Android | `payload.optDouble("level", -1.0)` | ✅ works |
| web | `payload.level` (fraction), `value` still read as a percentage | ✅ **fixed in 1.9.31** |
| Tizen | `payload.level` (fraction) | ✅ fixed in 1.9.31 — but see the note below on when the baseline may move |
| BrightSign | (the web player) | ✅ as web |

Three of the four players had a complete, working volume implementation that could not be driven,
because nobody checked the payload key against the sender. Fixed in 1.9.31: the fraction is now
canonical everywhere, and the scale is chosen by WHICH KEY arrived rather than by the magnitude of
the number (`1` is legal under both conventions, so guessing from the value is wrong for somebody).

`audio.volume` is back in the `web` and `brightsign` baselines as of 1.9.31, and **not** in the
`tizen` one. That asymmetry is the model, not an oversight — see
[When a baseline may move](#when-a-baseline-may-move).

### 2. Every #161 Tier-2 command was refused for the entire fleet — FIXED here

`lock_now`, `power_menu`, `status_bar`, `block_uninstall` and `unblock_uninstall` were gated on
`system.device_owner`. **No player declares that name** — not `PlayerCapabilities.kt`, not
`tizen/js/capabilities.js`, not `declaredCapabilities()`, not `st-bridge.js` — and no baseline
granted it. So `supports()` returned false for every device on every platform and all five commands
were refused, *including on the device-owner panels the whole feature was built for*. The dashboard
still drew the buttons, because `device-detail.js` gates that block on `device.tier === 2 ||` too,
so an operator on a real owner panel pressed "Lock now" and got a silent server-side refusal.

Fixed in `player-capabilities.js`: those five now accept `system.device_owner` **or**
`system.kiosk`. That is an exact stand-in, not a loose one — `PlayerCapabilities.kt` declares
`system.kiosk` under `if (isOwner)` and nothing else, which is precisely when `STPolicy`'s `owned()`
actions do anything, and no non-Android player declares it.

**Follow-up owned by Android:** `PlayerCapabilities.kt` should declare `system.device_owner` under
`if (isOwner)`, at which point the stand-in becomes redundant.

### 3. The capture bootstrap required the capability it creates — half FIXED here

`enable_system_capture` raises Android's MediaProjection consent dialog: it is how a panel *gains*
full-screen capture. It was gated on `remote.screenshot`, so the only panel that needs it — no
accessibility, no projection grant, therefore no declared `remote.screenshot` — was the one panel
that could not be sent it. The command is now ungated.

**Still broken, and it is a frontend change:** `device-detail.js` renders the button behind
`can('remote.screenshot')`, so it is still hidden on exactly those panels.

---

## Playback

No command routes to any `playback.*` capability and no dashboard control is gated on one, so these
describe content rendering. They are informational, and shown to the operator in the Info tab.

| capability | Android | Web | Tizen | BrightSign |
|---|---|---|---|---|
| `playback.video` | ✅ ExoPlayer (`MediaPlayerManager`) | ✅ `<video>` | ✅ AVPlay | ✅ hardware plane |
| `playback.image` | ✅ `ImageLoader` | ✅ | ✅ | ✅ |
| `playback.widget` | ✅ WebView | ✅ iframe | ✅ iframe | ✅ iframe |
| `playback.youtube` | ✅ WebView embed | ✅ IFrame API | ✅ iframe embed | ✅ IFrame API |
| `playback.zones` | ✅ `ZoneManager` | ✅ | ✅ | ✅ |
| `playback.transitions` | ✅ `TransitionCompositor` | ⚠️ declared only when the bundle loads (`transitionRuntimeReady()`) — a failed load hard-cuts rather than breaking playback | ✅ `transitions.js` | ⚠️ composites DOM over video; with hwz it may be **invisible over video** and degrade to a hard cut |
| `playback.pip` | ✅ `PipOverlay` | ✅ `#pipContainer` | ✅ `pip-overlay.js` | ⚠️ same hwz caveat as transitions |

## Audio

| capability | Android | Web | Tizen | BrightSign |
|---|---|---|---|---|
| `audio.mute` | ✅ `device:mute-changed` → `setVideoMuted`, incl. YouTube via the IFrame bridge | ✅ | ✅ incl. YouTube via `postMessage` | ✅ as web |
| `audio.volume` | ✅ `set_volume` reads `payload.level` | ✅ reads `payload.level` (1.9.31) | ✅ `applyVolume` reads `payload.level` (1.9.31, incl. `tizen.tvaudiocontrol`) | ✅ as web |

## Display

| capability | Android | Web | Tizen | BrightSign |
|---|---|---|---|---|
| `display.rotation` | ✅ native `rootView.rotation` — the ExoPlayer surface rotates with it | ✅ CSS transform | ✅ CSS + AVPlay `setDisplayRotation` for video | ⚠️ CSS cannot turn the hardware video plane; the host would have to (`roVideoMode`), and the page never calls `BS.setVideoMode` |
| `display.power` | ⚠️ conditional. `screen_off` needs owner / device-admin FORCE_LOCK / accessibility; `screen_on` is a **wake lock**, which works anywhere — but only since `812e89f`. On the fielded build `screen_on` is a logged no-op, which is why the Android baseline no longer claims this | ❌ a browser tab cannot power a panel — the overlay only paints black | ✅ both halves on every build, no signing needed: `showScreenOff()` / `clearScreenOff()`, plus the real panel API where `STDeviceControl` finds one | ⚠️ needs `hasHost()`. Media teardown always blanks; ❓ **CEC is unverified** — our XT245 resolves `@brightsign/cec` while the kernel logs `failed to get cec clock` and the display never responds |
| `display.resolution` | ❌ needs system/root | ❌ not addressable from a browser | ❌ no web-accessible mode setting on the TV profile | ⚠️ **declared but unreachable** — `st-bridge.js` exposes `setVideoMode`, the page never calls it, and no command maps to this capability |
| `display.brightness` (per-window dim, Tier 0) | ✅ `set_brightness` → `setWindowBrightness`, no privilege needed | ❌ | ❌ | ❌ |

⚠️ `PlayerCapabilities.kt` **does not declare `display.brightness`**, though `MainActivity` handles
`set_brightness` unconditionally. So an *updated* Android panel loses the per-window dim slider that
an un-updated one keeps via the baseline. See gap 2.

## Remote view and control

| capability | Android | Web | Tizen | BrightSign |
|---|---|---|---|---|
| `remote.screenshot` | ⚠️ `captureView` always (a real frame of the player's own view); full-screen only with accessibility or MediaProjection. Declared **only** for the full-screen path | ⚠️ canvas only — same-origin content, and the alpha probe rejects frames where no pixels arrived | ⚠️ `captureAndSend` captures **images only**; video and YouTube get an honest status card reading "Live preview unavailable for video / YouTube on Tizen" | ⚠️ `st-bridge.js` gates host framebuffer capture on **primary storage**; without a disk it falls back to canvas, which cannot read the video plane |
| `remote.stream` | ✅ | ✅ 1fps | ✅ 1s interval over `captureAndSend`, so the same image-only limit | ⚠️ as web |
| `remote.input` | ✅ `TouchInjector` — plain `dispatchTouchEvent`, no privilege | ✅ | ✅ `elementFromPoint().click()` + D-pad/volume keys | ✅ synthesised DOM events, needs no host |

## Lifecycle

| capability | Android | Web | Tizen | BrightSign |
|---|---|---|---|---|
| `system.restart_player` | ✅ `launch` / `refresh` | ✅ `location.reload()` | ✅ `location.reload()` via `STDeviceControl` | ⚠️ needs `hasHost()` so the host rebuilds the widget. **A page-initiated reload does not reliably bring an roHtmlWidget back** — that darkened a customer's panel on 2026-07-28, which is why neither `st-bridge.js` nor the baseline offers this without a host |
| `system.reboot` | ⚠️ **device owner only** (`STPolicy.reboot()`). Off-owner it degrades to an accessibility power *dialog*, which needs someone at the screen | ❌ a browser tab cannot reboot its host | ⚠️ only on a **partner-signed** panel where `STDeviceControl.capabilities().reboot` is true | ⚠️ `RebootSystem()` via the host |
| `system.self_update` | ✅ APK OTA (`UpdateChecker`), and `update` forces a check | ❌ the server deploys the player; there is nothing for it to update | ❌ a `.wgt` is installed by the panel, not the app | 💀 **for the dashboard button.** The host really does self-update — `autorun.brs` polls `CheckPackageUpdate` every `PKG_CHECK_MS` — but that is a host-side poll on a socket it is not listening to. The page declares `system.self_update` behind `hasHost()`, the dashboard renders "Force update", and `index.html` has **no `update` branch at all**. See gap 3 |

## Device management

Android device-owner territory. Everything here is ❌ elsewhere for the same reason — no equivalent
privilege model exists on those platforms — so the column is collapsed. Tizen and BrightSign both
decline these explicitly and in writing in their own capability modules.

| capability | Android | Web / Tizen / BrightSign |
|---|---|---|
| `system.kiosk` | ⚠️ owner-only. Off-owner `startLockTask()` is screen pinning, which prompts — unusable on a panel with no input | ❌ no device-owner concept |
| `system.brightness` | ⚠️ `WRITE_SETTINGS` **or** owner (`setSystemSetting`) | ❌ |
| `system.screen_timeout` | ⚠️ same gate as above | ❌ |
| `system.install_apk` | ⚠️ owner **or** a foreign DPC that delegated the install scope | ❌ not an APK platform |
| `system.shell` | ✅ declared unconditionally — it is an **app-UID** `sh -c`, not root, so it works at any tier. Handled in `WebSocketService` | ❌ |
| `system.time` | ⚠️ owner-only | ❌ |
| `system.device_owner` | 💀 **declared by nobody.** See the red section above | ❌ |

## Synchronisation and resilience

| capability | Android | Web | Tizen | BrightSign |
|---|---|---|---|---|
| `sync.clock` | ✅ `GroupScheduleController` | ✅ | ✅ `syncedNow()` + `schedule-eval.js` | ✅ as web |
| `sync.native` | ❌ no native protocol | ❌ | ❌ | ⚠️ `st-sync.js` / SyncManager, gated on module presence **and** BOS 8.2.10+ (below the floor the module can resolve and silently do nothing, which on a wall means every panel reports healthy while drifting). ❓ **unverified on hardware** |
| `offline.cache` | ✅ `ContentCache` + `DownloadCoordinator`, resumable (Range/If-Range), revision-keyed | ✅ service worker, resumable chunked prefetch, revision-keyed; declared only when a worker is genuinely **controlling** the page | ⚠️ `js/media-cache.js` caches media to `wgt-private` — **new at HEAD**, absent from the fielded build, and declared at runtime only where the platform grants storage | ❓ **unverified.** See gap 4 |

---

## Where the four declaration sites disagree with each other

| | Android | Web | Tizen | BrightSign |
|---|---|---|---|---|
| declaration site | `telemetry/PlayerCapabilities.kt` | `declaredCapabilities()` in `index.html` | `js/capabilities.js` | **`index.html` again** |

⚠️ **`brightsign/st-bridge.js` `computeCapabilities()` IS DEAD CODE.** It is exported as
`BS.capabilities`, and nothing calls it: `grep -n "BS\.[a-zA-Z]*(" server/player/index.html` lists
23 bridge calls and `capabilities` is not among them. The BrightSign declaration actually comes
from the web player's `declaredCapabilities()`, and the two disagree substantially:

| capability | `st-bridge.js` says | `index.html` actually declares | which is right |
|---|---|---|---|
| `offline.cache` | `navigator.serviceWorker` **exists** | a worker is **controlling** the page | index.html. The bridge's version is the exact lie that shipped on the XT245 |
| `remote.screenshot` | needs `probe.storage_present` | any 2d canvas | the bridge. A canvas cannot read the video plane |
| `remote.stream` | needs `probe.storage_present` | unconditional | the bridge |
| `system.self_update` | needs `probe.storage_present` | needs `hasHost()` | the bridge — staging `autorun.zip` needs a volume |
| `display.rotation` | needs a host (`roVideoMode`) | unconditional (CSS) | the bridge, for video |
| `display.power` | needs `CecClass` | needs `hasHost()` | roughly equivalent |
| `display.resolution` | host **or** `VideoOutputClass` | needs `hasHost()` | the bridge |
| `system.restart_player` | needs a host | unconditional | the bridge — see the 2026-07-28 incident |
| `sync.native` | module **and** OS ≥ 8.2.10 | `ScreenTinkerBSSync.available()`, which is **module presence only** | the bridge. `index.html` skips the firmware floor |

**`server/test/brightsign-capabilities.test.js` is 199 lines of thorough tests for this dead
function.** Every one passes, and none of them constrains what a BrightSign actually declares. That
is worse than no coverage: it reads as proof.

The fix is small and belongs to whoever owns those files — have `declaredCapabilities()` return
`BS.capabilities()` when `BS.isBrightSign()`, and the storage/firmware gating that was already
written and tested starts being true.

---

## Real gaps worth closing

Prioritised by how visible the failure is to an operator.

**Gaps 1, 2 and 5 are closed** (gap 1 shipped in 1.9.31; 2 and 5 are on
`fix/player-parity-small-gaps` and unreleased). ⚠️ **The baselines below have deliberately NOT been
moved** — per the rule in this document a baseline entry moves when the fix *reaches displays*,
which is the release AFTER the one carrying it. Moving them together would grant a capability to
every panel still running the old build.

⚠️ **Gaps 3 and 4 were implemented, audited, and REVERTED.** Both are still open, and both are now
known to be considerably more expensive than "small". Their rows record what the audit found, so the
next attempt starts from the traps rather than rediscovering them.

| # | gap | difficulty | why it matters |
|---|---|---|---|
| 1 | ✅ **`set_volume` payload mismatch** (`server/player/index.html`, `tizen/js/app.js`) — accept `level` (0..1) alongside `value` (0..100). | **trivial** — one line each | The volume slider is dead on 3 of 4 players. Highest visibility, lowest cost in the list. **Fixed and released in 1.9.31** (`volumeLevelFromCommand()`). |
| 2 | ✅ **`PlayerCapabilities.kt` under-declares.** Add `display.brightness` (Tier 0, `setWindowBrightness`, always available) and `system.device_owner` under `if (isOwner)`. | **trivial** | Updating an Android panel currently *loses* it the per-window dim slider, and keeps the Tier-2 stand-in in `player-capabilities.js` necessary. **Fixed** — both declared; the `system.kiosk` stand-in can retire one release after this ships. **The gap was wider than written**: `remote.screenshot` and `remote.stream` were gated on the accessibility service while `captureScreen()` falls through to `ScreenshotCapture.captureView`, a plain view draw with no permission check — so a Tier-0 panel *lost live view and screenshots by updating*, and a granted MediaProjection never became a capability at all (nothing re-declares on consent, so the operator granted it, capture started, and the server went on refusing). Both are now unconditional, matching the baseline's own reasoning. `display.power` remains conditional on purpose — see the DELIBERATE list in `player-parity-baselines.test.js`. |
| 3 | ❌ **REVERTED — BrightSign "Force update" is a dead button.** `index.html` has no `update` branch; the host self-updates on its own poll. | **NOT small — needs host work first** | Wiring the button to `CheckPackageUpdate` was tried and withdrawn. The update path is **synchronous and unbounded** (no `SetTimeout` on either transfer), so a slow failing download blocks the message loop past `WATCHDOG_MS` (120s), fabricating a crash event and rebuilding the widget. Worse, `MAX_ATTEMPTS_PER_VERSION` is 3 and the counter carries **no version binding**, so three presses on a bad link refuse that panel *every future version* until someone clears the registry by hand. `cfg.self_update` is not in the probe payload either, so an opted-out fleet shows a button guaranteed to do nothing while the dashboard toasts success — and `update` is allowed as a **group broadcast**, so one click can start N synchronous downloads. Prerequisites: a transfer timeout under the watchdog, a version-bound (or manual-exempt) attempt counter, a result message so the toast can tell the truth, and `self_update` in the probe. Until then, **withdrawing the claim is the cheaper honest fix.** |
| 4 | ❌ **REVERTED — `declaredCapabilities()` should defer to `BS.capabilities()` on BrightSign.** | **NOT small — the bridge's list is not a superset** | Deferring wholesale was tried and withdrawn: the two lists disagree in **both** directions. The bridge gates `remote.screenshot`/`remote.stream` on `storage_present` alongside `system.self_update`, but that reasoning is stale — the player captures via `@brightsign/screenshot` into **RAM** (`/tmp`) and falls back to canvas, so both work with no disk and deferring *removes working controls*. Only `system.self_update` is genuinely storage-gated. The bridge also declares `playback.transitions` unconditionally, where the page checks `transitionRuntimeReady()` — an over-declare on the one platform where the UMD/`nodejs_enabled` collision silently kills transitions. And `offline.cache` gets *looser*, not stricter: the bridge omits the page's `swRegistrationFailed` check. Compounding all of it, `probeHost`'s 3s timeout sets `answered = true`, so a late `probe-result` is discarded **for the page's lifetime** — and `autorun.brs` runs a blocking update check *before* entering the message loop, making a >3s answer plausible. A correct fix is a per-capability MERGE, not a wholesale hand-off, plus fixing the probe timeout. |
| 5 | ✅ **The capture-bootstrap button is hidden where it is needed** (`device-detail.js`, `can('remote.screenshot')`). | **small** | Server-side gating is fixed; the UI half is not. **Fixed** via `isAndroidDevice()`, mirroring `platformFamily()` in `server/lib/player-capabilities.js` — all four signals in the same order, since a Tizen TV registers `android_version: 'Tizen 6.5'` and an Android-test-only helper classifies every Samsung panel as Android. ⚠️ The gate is Android-and-nothing-else, **not** "Android that lacks `remote.screenshot`": `/api/devices/:id` ships `capabilitiesFor()`, which flattens declared and baseline into one array, and the android baseline *contains* `remote.screenshot` — so that condition hides the button from all ~440 undeclared panels. The dashboard cannot currently distinguish "declared" from "baseline-filled" at all; if a future gate needs that, the API must expose the raw declaration. |
| 6 | **Tizen `remote.screenshot` is images-only.** Video and YouTube return a status card. AVPlay has no readable surface for a canvas. | **hard**, possibly impossible | Honest today, but an operator checking a video panel gets a card instead of a picture. |
| 7 | **BrightSign transitions/PiP over video.** DOM composited over a hwz hardware plane may be invisible. The likely fix is `roVideoMode.SetGraphicsZOrder("front")`, deliberately not applied blind. | **medium**, ❓ **needs hardware** | Changing z-order blind risks hiding video entirely on a player that currently works. |
| 8 | **BrightSign offline caching is unproven either way.** See below. | ❓ **needs hardware** | |

### The BrightSign `offline.cache` question, stated honestly

A real XT245 on alpha exposes `navigator.serviceWorker`, and then never even fetches `sw.js`:
registration is refused, so there is no worker, no content cache and no offline playback. That unit
runs **BSN Supervisor** (`autorun.createdby = Supervisor 2.1.18.3`) rather than our
`brightsign/autorun.brs`, and Supervisor's widget has no `storage_path` — the setting our own host
script does set (`storage_path: "/cache"`, `storage_quota: "1073741824"`) and the precondition for a
widget having persistent storage at all.

So this is *very likely* a widget CONFIG issue rather than a platform limit. **It is unverified: no
one has yet watched a player running our package register a worker.** Until someone has, this
document does not claim it, the `brightsign` baseline does not grant it, and the player declares it
only when a worker is genuinely in control — a refused registration reports
`app_error/sw_unavailable` to the server rather than a `console.warn` on a display nobody has a
console for.

## Correctly impossible — do not "fix" these

- **`system.reboot` on web.** No API exists. A browser tab rebooting its host would be a browser
  vulnerability.
- **`display.power` on web.** The overlay is the honest maximum; the panel stays lit.
- **Device management off Android.** No equivalent privilege model exists on Tizen or BrightSign,
  and a web player has no device to manage.
- **`system.self_update` on web.** The player *is* the deployment; there is nothing to update.
- **`sync.native` off BrightSign.** It is BrightSign's own protocol, and the clock-derived one is
  the cross-platform answer that already works everywhere.
- **`display.resolution` off BrightSign.** No other platform exposes mode setting to an app.

---

## Baselines: what an un-updated display is assumed to be able to do

~446 fielded displays declare nothing and fall back to `BASELINE` in
`server/lib/player-capabilities.js`. Because v1.9.29 is the first build in which *any* player
declares anything, every display reading a baseline is running **v1.9.28 or older by construction**
— so each entry below is justified against `git show v1.9.28:<player source>`, not against HEAD.

`server/test/player-parity-baselines.test.js` pins these to the player sources.

### Corrections made in this pass

| baseline | change | evidence |
|---|---|---|
| `android` | **removed `display.power`** | v1.9.28 `MainActivity`: `"screen_on" -> Log.w("no privileged wake path on a non-rooted panel — no-op")`. The ON half is dead on 100% of fielded panels, and one capability renders **both** buttons. |
| `android` | **removed `system.reboot`** | `STPolicy.reboot()` requires device owner; off-owner v1.9.28 shows the accessibility power *dialog* — which on the accessibility-enabled panels common in this fleet paints that dialog **over the signage**. Owner provisioning is unreleased (#161 / PR #168 still open), so "device owner AND pre-1.9.29" is effectively an empty set. |
| `tizen` | **added `display.power`** | v1.9.28 `app.js` implements both halves with no signing and no panel API: `showScreenOff()` / `clearScreenOff()` + `keepAwake()`. Unlike Android, neither half is privilege-gated. Withholding it hid a working control on every Tizen panel. |
| `web` | **removed `audio.volume`, then RESTORED it in 1.9.31** | Removed when v1.9.28 `index.html` contained the string `set_volume` zero times. Restored once the handler landed — this player is served by the server, so there is no fielded build to lag behind. |
| `brightsign` | **removed `display.power`, `system.reboot`, `system.restart_player`, `offline.cache`** (and `audio.volume`, restored in 1.9.31 with `web`) | All five need a host bridge (`hasHost()`) or a service worker that a Supervisor-built widget refuses. `system.restart_player` is the 2026-07-28 panel-blackout path. `offline.cache` is the documented lie this whole model exists to stop. |

### When a baseline may move

A baseline describes what an **un-updated** display can do, so the question "has this shipped?"
has two different answers depending on how the player reaches the screen.

**Served by the server — `web`, `brightsign`.** The player is a document this server hands out. A
display running against this build *is* running this build's player; there is no such thing as a
browser panel stuck on last release's. So the baseline moves the moment the server ships the fix,
and holding it back hides a control that already works. `test/player-parity-baselines.test.js`
judges these two against the working tree, in **both** directions.

**Shipped as a device artifact — `android`, `tizen`.** The player is an APK or a `.wgt` sitting on
the panel. Cutting a release puts nothing on any screen; a panel updates when somebody updates it,
and this repo cannot know how many are still back on which build. These are judged against the
**previous release**, and only in the over-claim direction: "the baseline claims it, so the shipped
player had better implement it" is always worth failing on, while "HEAD gained the handler, so add
it to the baseline" is a guess about the fleet, not a fact about it. A panel that HAS updated
declares its own capabilities and never reads the baseline at all.

The cost of the one-directional rule is that a stale entry can sit here after the artifact really
has reached the fleet. That is a judgement call about panels, so a person makes it in
`server/lib/player-capabilities.js` and records why — which is what the Tizen `audio.volume` note
there is doing right now.

> This distinction was learned the hard way. The test used to read "shipped" as *the newest tag*,
> which is HEAD on a release commit — so tagging 1.9.31 flipped every biconditional at once and
> demanded a baseline change for displays that could not possibly have the fix yet. The build went
> red naming a baseline, with nothing in the diff to explain it.

### Consequence, deliberately accepted

`server/services/scheduler.js` gates the nightly scheduled reboot on `system.reboot`. Removing it
from the Android baseline means scheduled reboots now **no-op for undeclared Android panels**
instead of logging `scheduled reboot fired` for a panel that never rebooted. That log line is the
stated reason the gate exists; skipping is the honest answer, and an owner panel on v1.9.29+
declares `system.reboot` for itself and is unaffected.

### The resulting baselines

| capability | android | tizen | brightsign | web |
|---|---|---|---|---|
| `playback.*` (all 7) | ✅ | ✅ | ✅ | ✅ |
| `audio.mute` | ✅ | ✅ | ✅ | ✅ |
| `audio.volume` | ✅ | ❌ the fielded `.wgt` has no handler | ✅ since 1.9.31 (runs the served player) | ✅ since 1.9.31 |
| `display.rotation` | ✅ | ✅ | ⚠️ graphics only | ✅ |
| `display.power` | ❌ `screen_on` is a no-op | ✅ | ❌ needs host | ❌ |
| `display.brightness` | ✅ Tier 0, since v1.9.10 | ❌ | ❌ | ❌ |
| `remote.screenshot` / `remote.stream` | ✅ view capture | ✅ images only | ❌ no video plane | ✅ |
| `remote.input` | ✅ | ✅ | ✅ | ✅ |
| `system.restart_player` | ✅ | ✅ | ❌ widget may not return | ✅ |
| `system.self_update` | ✅ | ❌ | ❌ needs host | ❌ |
| `system.reboot` | ❌ owner-only | ❌ | ❌ needs host | ❌ |
| `sync.clock` | ✅ | ✅ | ✅ | ✅ |
| `offline.cache` | ✅ | ❌ playlist JSON only | ❌ ❓ unverified | ✅ |

Everything conditional at runtime on every platform that has it at all — `system.kiosk`,
`system.brightness`, `system.screen_timeout`, `system.install_apk`, `system.shell`, `system.time`,
`system.device_owner`, `sync.native`, `display.resolution` — is absent from **every** baseline, and
a test enforces that.

## What is tested, and what cannot be

`server/test/player-parity-baselines.test.js` reads the player sources and fails when they and the
claims disagree:

- every baseline and command-map name is in the vocabulary, and no baseline has duplicates;
- **the dead-button rule** — every gated command has a branch in some player;
- **the unreachable-capability rule** — every gating capability is either declared by some player's
  source or granted by some baseline. *This is the test that would have caught the
  `system.device_owner` bug*;
- a device-owner Android panel can actually be sent all five Tier-2 commands, and an ordinary one is
  still refused them **by name**;
- `audio.volume` and `offline.cache` are **biconditional** against the player sources, so a fix in a
  player fails the test until the baseline is updated;
- no baseline claims a conditional capability, and the BrightSign baseline claims nothing behind
  `hasHost()`;
- every capability-shaped string quoted in any player is one the server knows — the server's parser
  *drops* unknown names, so a typo silently removes a control rather than raising anything.

**Not testable from source, and asserted nowhere:** whether CEC reaches a real display; whether a
widget built by our own `autorun.brs` is permitted to register a service worker; whether SyncManager
genuinely holds a wall in frame lock; whether transitions and PiP are visible over a hwz video
plane. Each is marked ❓ above and needs hardware.