refactor(ui): defer every classic script, keep boot() on DOMContentLoaded (R3a)

Puts every external `<script>` in the v3 shell into the deferred queue, and
keeps each script's boot() firing at DOMContentLoaded exactly as it does today.
Behaviourally a no-op; it is what makes the ES-module flips safe.

WHY. `type="module"` defers execution to after HTML parse. Classic-`defer` and
module scripts share ONE "execute after parsing" list and run in DOCUMENT ORDER,
but a plain classic script runs DURING parse — ahead of all of them. So the
moment capabilities.js becomes a module while app.js is still plain, app.js runs
FIRST, and its 11 top-level `window.feedBack.on(...)` calls (app.js:6245-6722)
hit a bare `{}` — `_ensureFeedBackEventBus()` (capabilities.js:33), which
attaches .on/.emit/.off, would not have run yet. TypeError, app.js dies
mid-parse. Deferring everything now keeps document order == execution order
through the rest of the migration.

THE CATCH (Codex preflight caught this — a real ordering change). 22 scripts
guard their boot with `if (document.readyState === 'loading')`. A deferred
script runs at readyState 'interactive', so that test is FALSE and the else-branch
fires boot() immediately, at the script's position in document order — instead of
at DOMContentLoaded, after every script has evaluated.

That matters far more than one call site: a scan of the shell's scripts found
**43 forward references** where a script's boot() reads a global that a LATER
script defines (shell.js -> profile.js's window.v3Onboarding, songs.js ->
settings.js's window._confirmDialog, badges.js -> songs.js's
window.displayTuningName, ...). Every one of them resolves today only because
all boots happen at DOMContentLoaded. So the guards now treat 'interactive' as
not-ready (`!== 'complete'`), restoring that exactly.

Codex's specific finding (first-run onboarding silently skipped) did NOT
reproduce — shell.js's boot() awaits /api/profile, and that yield lets the
remaining deferred scripts run first. But the race it described is real, the
guard is silent when it fails (`&& window.v3Onboarding`), and the other 42
forward refs have no such await protecting them. Fixed at the root rather than
at the one site.

VERIFIED. A/B against origin/main on a fresh profile, 13 probes (onboarding
overlay, v3Onboarding/v3Songs/v3Profile/fbNotify/v3Badges/uiPrompt/showScreen,
bus, capabilities.version, createHighway, plugin scripts, mounted screens):
IDENTICAL, zero console/page errors on both. pytest 2396, node 1028/1028,
ESLint 0 errors, Codex 0.

New guard: test_every_external_script_defers_so_document_order_is_execution_order
fails if any external tag is plain classic — verified to fail on a single
reverted tag, so it actually bites.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

static/app.js

@@ -6638,7 +6638,9 @@ window.feedBack.on('screen:changed', (ev) => {
     if (id === 'player') _hideResumePill();
     else _maybeShowResumePill();
 });
-if (document.readyState === 'loading') {
+// `defer` runs this at readyState 'interactive' — later scripts have not
+// evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+if (document.readyState !== 'complete') {
     document.addEventListener('DOMContentLoaded',
         () => { try { _maybeShowResumePill(); } catch (_) {} }, { once: true });
 } else {

static/audio-mixer.js

@@ -519,7 +519,9 @@ window.feedBack.audio = Object.assign(window.feedBack.audio || {}, {
     readSongVolume: _readSongVolume,
 });
 
-if (document.readyState === 'loading') {
+// `defer` runs this at readyState 'interactive' — later scripts have not
+// evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+if (document.readyState !== 'complete') {
     document.addEventListener('DOMContentLoaded', _init);
 } else {
     _init();

static/capabilities/interface-scale.js

@@ -111,7 +111,9 @@
 
     // Announce once after the document parses, so any listener wired during page
     // load can sync without special-casing (consumers may also just call get()).
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', announce, { once: true });
     } else {
         announce();

static/v3/badges.js

@@ -592,6 +592,8 @@
             sm.on('working-tuning-changed', () => renderInstrument());
         }
     }
-    if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', boot, { once: true });
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') document.addEventListener('DOMContentLoaded', boot, { once: true });
     else boot();
 })();

static/v3/dashboard.js

@@ -271,6 +271,8 @@
         sm.on('v3:profile-updated', () => render());
     }
     function boot() { render(); }
-    if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', boot, { once: true });
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') document.addEventListener('DOMContentLoaded', boot, { once: true });
     else boot();
 })();

static/v3/feedbarcade.js

@@ -273,7 +273,9 @@
         // the stage observer attaches.
         window.addEventListener('feedBack-minigames-ready', () => { ensureStageObserver(); refresh(); });
     }
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', boot, { once: true });
     } else {
         boot();

static/v3/index.html

@@ -99,23 +99,39 @@
     <link rel="stylesheet" href="/static/tour-engine.css">
     <!-- v0.3.0 shell styles (radial-gradient bg, custom scrollbars). -->
     <link rel="stylesheet" href="/static/v3/v3.css">
+    <!-- EVERY external script below is `defer`. Do not add a plain one.
+         `defer` and `type="module"` scripts share a single "execute after
+         parsing" list and run in DOCUMENT ORDER; a plain classic script runs
+         DURING parse, ahead of all of them. So one plain tag would jump the
+         queue — and once the capabilities become modules (they defer), a
+         still-plain app.js would run BEFORE the bus exists and die on its
+         top-level `window.feedBack.on(...)` calls. Keeping every tag deferred
+         is what preserves this file's order through the ES-module migration.
+         Enforced by test_every_external_script_defers_so_document_order_is_execution_order.
+
+         The scripts themselves boot on DOMContentLoaded, which fires only after
+         all of the above have evaluated — that is what lets a script's boot()
+         use a global another script defines further down this list (there are
+         ~43 such forward references). Their readyState guards therefore treat
+         'interactive' as not-ready; see the note at each one. -->
+
     <!-- Diagnostics console capture must wrap console.* before any other
          script logs anything; load it as early as possible. See
          docs/diagnostics-bundle-spec.md (feedBack#166). -->
-    <script src="/static/diagnostics.js"></script>
-    <script src="/static/capabilities.js"></script>
-    <script src="/static/capabilities/library.js"></script>
-    <script src="/static/capabilities/tuning.js"></script>
-    <script src="/static/capabilities/working-tuning.js"></script>
-    <script src="/static/capabilities/audio-session.js"></script>
-    <script src="/static/capabilities/audio-effects.js"></script>
-    <script src="/static/capabilities/playback.js"></script>
+    <script defer src="/static/diagnostics.js"></script>
+    <script defer src="/static/capabilities.js"></script>
+    <script defer src="/static/capabilities/library.js"></script>
+    <script defer src="/static/capabilities/tuning.js"></script>
+    <script defer src="/static/capabilities/working-tuning.js"></script>
+    <script defer src="/static/capabilities/audio-session.js"></script>
+    <script defer src="/static/capabilities/audio-effects.js"></script>
+    <script defer src="/static/capabilities/playback.js"></script>
     <!-- fee[dB]ack v0.3.0: ui.library-card-injection capability (plugin card actions). -->
-    <script src="/static/capabilities/library-card-actions.js"></script>
-    <script src="/static/capabilities/visualization.js"></script>
-    <script src="/static/capabilities/note-detection.js"></script>
-    <script src="/static/capabilities/midi-input.js"></script>
-    <script src="/static/capabilities/interface-scale.js"></script>
+    <script defer src="/static/capabilities/library-card-actions.js"></script>
+    <script defer src="/static/capabilities/visualization.js"></script>
+    <script defer src="/static/capabilities/note-detection.js"></script>
+    <script defer src="/static/capabilities/midi-input.js"></script>
+    <script defer src="/static/capabilities/interface-scale.js"></script>
 </head>
 <body class="h-screen flex overflow-hidden bg-fb-sidebar text-fb-text font-display">
 
@@ -1225,64 +1241,64 @@
     </main>
     <!-- /#v3-main -->
 
-    <script src="/static/highway.js"></script>
-    <script src="/static/vendor/lottie.min.js"></script>
-    <script src="/static/lottie-api.js"></script>
-    <script src="/static/app.js"></script>
-    <script src="/static/audio-mixer.js"></script>
-    <script src="/static/vendor/shepherd.min.js"></script>
-    <script src="/static/tour-engine.js"></script>
+    <script defer src="/static/highway.js"></script>
+    <script defer src="/static/vendor/lottie.min.js"></script>
+    <script defer src="/static/lottie-api.js"></script>
+    <script defer src="/static/app.js"></script>
+    <script defer src="/static/audio-mixer.js"></script>
+    <script defer src="/static/vendor/shepherd.min.js"></script>
+    <script defer src="/static/tour-engine.js"></script>
     <!-- fee[dB]ack v0.3.0 shell: brand helper, then the shell (sidebar/topbar/
          routing). Loaded after app.js/audio-mixer so window.showScreen and
          window.feedBack(.audio) exist; dashboard.js is filled in prompt 13. -->
-    <script src="/static/v3/brand.js"></script>
-    <script src="/static/v3/shell.js"></script>
+    <script defer src="/static/v3/brand.js"></script>
+    <script defer src="/static/v3/shell.js"></script>
     <!-- Progression (spec 010): theme-core before profile.js so the equipped
          theme/avatar frame apply with the first badge render; progression-core
          registers the `progression` capability owner + window.v3Progression. -->
-    <script src="/static/v3/theme-core.js"></script>
-    <script src="/static/v3/progression-core.js"></script>
-    <script src="/static/v3/notifications.js"></script>
-    <script src="/static/v3/profile.js"></script>
-    <script src="/static/v3/progress.js"></script>
-    <script src="/static/v3/shop.js"></script>
-    <script src="/static/v3/tuner-core.js"></script>
-    <script src="/static/v3/badges.js"></script>
-    <script src="/static/v3/stats-recorder.js"></script>
-    <script src="/static/v3/live-performance-hud.js"></script>
-    <script src="/static/v3/scoreboard-pref.js"></script>
-    <script src="/static/v3/venue-viz.js"></script>
-    <script src="/static/v3/venue-instrument-pov.js"></script>
+    <script defer src="/static/v3/theme-core.js"></script>
+    <script defer src="/static/v3/progression-core.js"></script>
+    <script defer src="/static/v3/notifications.js"></script>
+    <script defer src="/static/v3/profile.js"></script>
+    <script defer src="/static/v3/progress.js"></script>
+    <script defer src="/static/v3/shop.js"></script>
+    <script defer src="/static/v3/tuner-core.js"></script>
+    <script defer src="/static/v3/badges.js"></script>
+    <script defer src="/static/v3/stats-recorder.js"></script>
+    <script defer src="/static/v3/live-performance-hud.js"></script>
+    <script defer src="/static/v3/scoreboard-pref.js"></script>
+    <script defer src="/static/v3/venue-viz.js"></script>
+    <script defer src="/static/v3/venue-instrument-pov.js"></script>
     <!-- venue-mood-fx must load before venue-scene-3d: the scene bridge reads
          window.v3VenueMoodFx.getMotion() synchronously at boot when the saved
          viz is 'venue'; loading it after falls back to 'subtle' and ignores a
          saved 'off'/'full' motion preference on first paint. -->
-    <script src="/static/v3/venue-mood-fx.js"></script>
-    <script src="/static/v3/venue-scene-3d.js"></script>
-    <script src="/static/v3/playlists.js"></script>
-    <script src="/static/v3/audio-routing.js"></script>
-    <script src="/static/v3/live-guitar-tone-source.js"></script>
-    <script src="/static/v3/pedal-cables.js"></script>
-    <script src="/static/v3/plugins-page.js"></script>
-    <script src="/static/v3/card-actions-core.js"></script>
+    <script defer src="/static/v3/venue-mood-fx.js"></script>
+    <script defer src="/static/v3/venue-scene-3d.js"></script>
+    <script defer src="/static/v3/playlists.js"></script>
+    <script defer src="/static/v3/audio-routing.js"></script>
+    <script defer src="/static/v3/live-guitar-tone-source.js"></script>
+    <script defer src="/static/v3/pedal-cables.js"></script>
+    <script defer src="/static/v3/plugins-page.js"></script>
+    <script defer src="/static/v3/card-actions-core.js"></script>
     <!-- Before songs.js: the songs toolbar calls the match-review chip hook
          on build, so the module must already be registered. -->
-    <script src="/static/v3/match-review.js"></script>
+    <script defer src="/static/v3/match-review.js"></script>
     <!-- Before songs.js: the drawer art click + card ⋮ "Change cover…" open
          the cover picker (window.__fbOpenImagePicker). -->
-    <script src="/static/v3/image-picker.js"></script>
-    <script src="/static/v3/songs.js"></script>
-    <script src="/static/v3/lessons.js"></script>
-    <script src="/static/v3/dashboard.js"></script>
-    <script src="/static/v3/settings.js"></script>
-    <script src="/static/v3/interface-size-ui.js"></script>
+    <script defer src="/static/v3/image-picker.js"></script>
+    <script defer src="/static/v3/songs.js"></script>
+    <script defer src="/static/v3/lessons.js"></script>
+    <script defer src="/static/v3/dashboard.js"></script>
+    <script defer src="/static/v3/settings.js"></script>
+    <script defer src="/static/v3/interface-size-ui.js"></script>
     <!-- First-run home tour: spotlights the home cards via the shared tour
          engine (tour-engine.js, loaded above). Auto-runs once after onboarding
          (triggered from profile.js finish()); replayable from the "?" menu. -->
-    <script src="/static/v3/onboarding-tour.js"></script>
-    <script src="/static/v3/interface-size-nudge.js"></script>
-    <script src="/static/v3/feedbarcade.js"></script>
-    <script src="/static/v3/player-chrome.js"></script>
+    <script defer src="/static/v3/onboarding-tour.js"></script>
+    <script defer src="/static/v3/interface-size-nudge.js"></script>
+    <script defer src="/static/v3/feedbarcade.js"></script>
+    <script defer src="/static/v3/player-chrome.js"></script>
     <script>
         // Navbar scroll effect
         window.addEventListener('scroll', () => {

static/v3/interface-size-nudge.js

@@ -71,7 +71,9 @@
         setTimeout(maybeNudge, 4000);
     }
 
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', start, { once: true });
     } else {
         start();

static/v3/interface-size-ui.js

@@ -45,7 +45,9 @@
     // Settings markup is static, but re-sync when settings.js signals it wired.
     document.addEventListener('v3:settings-rendered', function () { sync(); });
 
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', function () { sync(); }, { once: true });
     } else {
         sync();

static/v3/live-guitar-tone-source.js

@@ -94,7 +94,9 @@
     }
 
     if (typeof document !== 'undefined') {
-        if (document.readyState === 'loading') {
+        // `defer` runs this at readyState 'interactive' — later scripts have not
+        // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+        if (document.readyState !== 'complete') {
             document.addEventListener('DOMContentLoaded', init);
         } else {
             init();

static/v3/live-performance-hud.js

@@ -303,7 +303,9 @@
             const sm = root && root.feedBack;
             if (sm) bindRuntime(sm);
         };
-        if (document.readyState === 'loading') {
+        // `defer` runs this at readyState 'interactive' — later scripts have not
+        // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+        if (document.readyState !== 'complete') {
             document.addEventListener('DOMContentLoaded', boot);
         } else {
             boot();

static/v3/match-review.js

@@ -913,7 +913,9 @@
         });
     }
 
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', () => {
             wireSettingsCard();
             wireScreenTeardown();

static/v3/player-chrome.js

@@ -362,6 +362,8 @@
         syncActivation();
     }
 
-    if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', init);
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') document.addEventListener('DOMContentLoaded', init);
     else init();
 })();

static/v3/playlists.js

@@ -440,6 +440,8 @@
         });
     }
     function boot() { renderPlaylists(); renderSaved(); }
-    if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', boot, { once: true });
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') document.addEventListener('DOMContentLoaded', boot, { once: true });
     else boot();
 })();

static/v3/plugins-page.js

@@ -579,6 +579,8 @@
     }, { passive: true });
 
     function boot() { render(); }
-    if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', boot, { once: true });
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') document.addEventListener('DOMContentLoaded', boot, { once: true });
     else boot();
 })();

static/v3/profile.js

@@ -792,7 +792,9 @@
             });
         }
     }
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', boot, { once: true });
     } else {
         boot();

static/v3/progress.js

@@ -320,7 +320,9 @@
             });
         }
     }
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', boot, { once: true });
     } else {
         boot();

static/v3/progression-core.js

@@ -241,7 +241,9 @@
     };
 
     _registerOwner();
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', () => { refresh(); }, { once: true });
     } else {
         refresh();

static/v3/settings.js

@@ -200,7 +200,9 @@
         });
     }
 
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', init, { once: true });
     } else {
         init();

static/v3/shell.js

@@ -399,7 +399,9 @@
         setTimeout(refreshHomeTitle, 700);
     }
 
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', boot, { once: true });
     } else {
         boot();

static/v3/shop.js

@@ -203,7 +203,9 @@
             });
         }
     }
-    if (document.readyState === 'loading') {
+    // `defer` runs this at readyState 'interactive' — later scripts have not
+    // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+    if (document.readyState !== 'complete') {
         document.addEventListener('DOMContentLoaded', boot, { once: true });
     } else {
         boot();

static/v3/venue-mood-fx.js

@@ -511,7 +511,9 @@
             const sm = root && root.feedBack;
             if (sm) bindRuntime(sm);
         };
-        if (document.readyState === 'loading') {
+        // `defer` runs this at readyState 'interactive' — later scripts have not
+        // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+        if (document.readyState !== 'complete') {
             document.addEventListener('DOMContentLoaded', boot);
         } else {
             boot();

static/v3/venue-scene-3d.js

@@ -242,7 +242,9 @@
 
     if (typeof document !== 'undefined') {
         const boot = () => bindRuntime();
-        if (document.readyState === 'loading') {
+        // `defer` runs this at readyState 'interactive' — later scripts have not
+        // evaluated yet, so wait for DOMContentLoaded (see static/v3/index.html).
+        if (document.readyState !== 'complete') {
             document.addEventListener('DOMContentLoaded', boot);
         } else {
             boot();

tests/test_plugin_runtime_idempotence.py

@@ -1,3 +1,4 @@
+import re
 from pathlib import Path
 
 import pytest
@@ -71,13 +72,39 @@ def test_capability_visualizer_waits_for_registry_instead_of_hard_error():
 def test_app_shell_loads_capability_registry_before_app_runtime():
     source = (ROOT / "static" / "v3" / "index.html").read_text(encoding="utf-8")
 
-    assert '<script src="/static/capabilities.js"></script>' in source
-    assert '<script src="/static/capabilities/library.js"></script>' in source
+    assert re.search(r'<script[^>]+src="/static/capabilities\.js"', source)
+    assert re.search(r'<script[^>]+src="/static/capabilities/library\.js"', source)
     assert source.index('/static/diagnostics.js') < source.index('/static/capabilities.js')
     assert source.index('/static/capabilities.js') < source.index('/static/capabilities/library.js')
     assert source.index('/static/capabilities/library.js') < source.index('/static/app.js')
 
 
+def test_every_external_script_defers_so_document_order_is_execution_order():
+    """The shell's scripts must all execute in document order.
+
+    `capabilities.js` builds the `window.feedBack` bus and must run before
+    `app.js`, which calls `window.feedBack.on(...)` at top level. Today document
+    order gives that for free, because every script is a parse-time classic one.
+
+    That guarantee survives the ES-module migration ONLY while no script is a
+    *plain* classic script: `defer` and `type="module"` scripts share one
+    "execute after parsing" list and run in document order, but a plain classic
+    script runs DURING parse — ahead of every deferred one. So the moment
+    capabilities.js becomes a module while app.js is still plain, app.js runs
+    first and `window.feedBack.on` is undefined.
+
+    Pinning "no plain external scripts" is what keeps that from silently
+    regressing as tags flip to type="module" one at a time.
+    """
+    source = (ROOT / "static" / "v3" / "index.html").read_text(encoding="utf-8")
+
+    plain = [
+        tag for tag in re.findall(r'<script\b[^>]*\bsrc=[^>]*>', source)
+        if 'defer' not in tag and 'async' not in tag and 'type="module"' not in tag
+    ]
+    assert not plain, f"external scripts that would jump the deferred queue: {plain}"
+
+
 def test_capability_registry_exposes_claim_dispatch_and_ready_contracts():
     source = (ROOT / "static" / "capabilities.js").read_text(encoding="utf-8")