Piano synth · mimo-v2.6-pro

Let me start by checking the working directory and the tone.min.js file.

Let me check the Tone version to know API (e.g., Tone.Synth with ADSR, Tone.getTransport etc.). Let's grep for version.

Maybe version is like "14.7.77". Let's grep for "14.7".

Tone.js 14.8.49. API: `Tone.start()`, `Tone.Synth`, `Tone.PolySynth`, `Tone.Destination`, `Tone.getContext()`. PolySynth defaults to 32 voices in v14.8? Actually PolySynth default voices = 32 in newer versions. But requirement says "support at least three simultaneous notes" — I'll use PolySynth with voices set, or manage individual Synth voices myself. Actually managing individual Synth voices per note gives better control of press/release per key. But PolySynth handles release properly with `triggerRelease(note)`.

Simplest robust: PolySynth(Tone.Synth) with options oscillator (e.g., "fatsawtooth" or "triangle"), envelope ADSR: attack 0.02, decay 0.1, sustain 0.6, release 0.8. Set `polyphony` via `new Tone.PolySynth(Tone.Synth, { ... })` — in v14.8 PolySynth constructor takes (voice, options) and options applies to voice. Max voices default 32.

Requirement: "Prevent keyboard auto-repeat from creating duplicate sustained voices." Use a Set of active notes; if already active, ignore repeat (event.repeat check or set membership).

"Release held voices when the pointer is released outside a key or the window loses focus" — handle pointerup on window (release all pointer-held notes), pointerleave/pointercancel, blur -> release all.

Use pointer events for mouse/touch: pointerdown on key -> start, pointerup/pointerenter? Requirement only says "Pressing a screen key or its computer key starts the note; releasing it starts the envelope's release phase." Also highlight keys while held. Also possibly pointer drag across keys? Not required. Keep it simple: pointerdown starts, pointerup anywhere releases (all pointer-held notes or tracked per pointerId). I'll track active notes with sources (pointerId or 'key:code') so each source releases its own note; but simpler: track map of note -> set of sources; release when all sources released. Let's implement:

- activeNotes: Map note -> { sources:Set, }.
- startNote(note, source): if sources empty overall (new), trigger attack; add source; add highlight class.
- releaseNote(note, source): remove source; if empty -> triggerRelease(note), remove highlight.
- releaseAll(source) or releaseAll() for blur.

Keyboard: keydown with e.repeat check and a Set of pressed codes; also ignore when target is input (not needed). Use code mapping: KeyA, KeyW, KeyS, KeyE, KeyD, KeyF, KeyT, KeyG, KeyY, KeyH, KeyU, KeyJ, KeyK → notes C4..C5.

Notes: C4, C#4, D4, D#4, E4, F4, F#4, G4, G#4, A4, A#4, B4, C5. Display as "C4", "C♯4"/"C#4" labels. Computer keys displayed on keys too and in a legend.

Layout: white keys C4 D4 E4 F4 G4 A4 B4 C5 = 8 white keys. Black keys between: C#4 (after C), D#4 (after D), F#4 (after F), G#4 (after G), A#4 (after A). No black between E-F and B-C. Correct positions.

Positioning: container width e.g. 8 white keys * 90px = 720px. Black key width ~56px, positioned at left = (whiteIndex+1)*90 - 28 for C# (after white index 0), etc.

Use absolute positioning inside a keyboard div with position relative, height 260px.

Audio activation: overlay with "Click to enable audio" button; on click `await Tone.start()`, then hide overlay and show status "Audio running — Context state: running". Log to console.

Highlight: CSS class .active on key, different color for white/black keys.

Also: pressing key should start; releasing computer key starts release. Note: multiple keys can be held.

Let me write the HTML now.

For the PolySynth: `new Tone.PolySynth(Tone.Synth, { oscillator: { type: "fatsawtooth", count: 3, spread: 20 }, envelope: { attack: 0.02, decay: 0.15, sustain: 0.5, release: 0.9 } })`. In v14, PolySynth options include voice options; `maxPolyphony` set separately: `poly.maxPolyphony = 32`. Actually the constructor signature in v14.8: `new Tone.PolySynth(Tone.Synth, {voice options})`. Setting `poly.maxPolyphony = 8` works. Good.

Connect through a filter/reverb? Keep simple: PolySynth -> Tone.Destination, maybe a gentle lowpass and a bit of reverb via Tone.Reverb requires async generate — Tone.Reverb's ready promise. Avoid to keep offline-safe; use Tone.Filter + Tone.Gain only (no network). Maybe add Tone.FeedbackDelay? Keep simple: Filter (lowpass 4000) -> Destination.

Also handle "Pressing a screen key ... starts the note; releasing it starts the envelope's release phase" — triggerAttack with velocity, triggerRelease.

Note frequency: use note names directly with Tone (triggerAttack("C4")).

Let me also add a small "status" area showing active notes count and context state.

Handle pointer: on key elements, `pointerdown` with `e.preventDefault()`, setPointerCapture? If we capture pointer on the key, pointerup fires on that key even if outside — but requirement says "Release held voices when the pointer is released outside a key" — that means on window pointerup we release pointer-held notes. If we use pointer capture, pointerup on the key fires even outside — still releases. But better to handle at window level: window pointerup -> release all notes held by pointers. That satisfies "released outside a key". Also handle pointercancel and pointerleave of document (pointer leaving window). Also `blur` and `visibilitychange` -> release everything.

Multi-touch: track by pointerId sources. Fine.

Also prevent context menu maybe. Also drag: allow glissando? Not required; but could add pointerenter while pointer down to move between keys. Skip — extra complexity but nice. I'll skip to stay safe? Actually glissando adds risk of stuck notes. Skip.

Now write file.

For labels: each white key shows note name + computer key letter. Black keys show note name + letter, smaller.

Legend mapping display: list of "A → C4" etc.

Let me write index.html.

Key layout data:
notes array with: note, label (e.g., "C4"), type white/black, computerKey 'A', code 'KeyA', whiteIndex for black positioning.

White keys: C4(A), D4(S), E4(D), F4(F), G4(H)... wait mapping: A W S E D F T G Y H U J K in order to those 13 notes:
A=C4, W=C#4, S=D4, E=D#4, D=E4, F=F4, T=F#4, G=G4, Y=G#4, H=A4, U=A#4, J=B4, K=C5. Good.

Now write.

For the audio gate overlay: a button that on click awaits Tone.start() then creates synth (create synth lazily after start). Set status text.

Also handle Tone context resume if suspended.

JS structure:

```js
const NOTES = [ {note:'C4', label:'C4', key:'A', code:'KeyA', type:'white', whiteIndex:0}, ... ];
```

Build DOM.

State:
```js
const activeSources = new Map(); // note -> Set of sources
let audioReady = false;
let synth = null;
```

startNote(note, source) { if(!activeSources.has(note)) activeSources.set(note,new Set()); const s = activeSources.get(note); if (s.size===0 && audioReady) synth.triggerAttack(note, Tone.now(), velocity); s.add(source); updateHighlight(note); }
Actually if s.size>0 already (another source holds it) don't retrigger.

releaseNote(note, source) { const s = activeSources.get(note); if(!s || !s.has(source)) return; s.delete(source); if(s.size===0){ activeSources.delete(note); if(audioReady) synth.triggerRelease(note); } updateHighlight }

releaseAll(source=null) { for each note: if source===null -> release all sources; else release that source. }

Keyboard: keydown -> if e.repeat return; if activeCodes.has(code) return; activeCodes.add(code); startNote(note, 'kbd:'+code). keyup -> activeCodes.delete(code); releaseNote(note,'kbd:'+code).

Pointer: key.addEventListener('pointerdown', e => { e.preventDefault(); if(e.button!==0 && e.pointerType==='mouse') return; startNote(note, 'ptr:'+e.pointerId); });
window pointerup/pointercancel -> releaseAll('ptr:'+e.pointerId) ... but simpler: on window 'pointerup', release all pointer sources for that pointerId. Also handle pointer leaving window: 'pointerleave' on document? Use window 'pointerup' and 'pointercancel' and also 'blur'. Additionally when pointer is released outside a key, window pointerup still fires (since pointerup goes to the element under pointer... wait, without capture, the pointerup event targets the element under the pointer at release time, and it bubbles up to window). Yes it bubbles to window regardless of which element. Good.

Also add pointer capture? Not needed.

Also handle mouse pointerdown on the key with preventDefault to avoid text selection/drag.

Blur: window.addEventListener('blur', () => releaseAll()); document.addEventListener('visibilitychange', ...).

Highlight: keyEl.classList.toggle('active', activeSources.has(note) && size>0).

Update status bar: active note count.

Now styling: dark background, gradient, nice look. Keyboard width responsive: use a container with fixed px width scaled via CSS transform? Simpler: keyboard width in px (720) but centered; on small screens could overflow. Use `--white-w` and container width 100% max 760px with flex white keys and black keys positioned by percentage. Percentage-based positioning: black key left = ((whiteIndex+1)/8*100)% minus half black width in %. That's responsive. Use black width as % of container: e.g., 3.4% of container? Let's do: white keys flex:1 each in a flex row; black keys absolutely positioned with left: calc((whiteIndex+1) * 12.5% ) and transform: translateX(-50%), width: 7.5% of keyboard width (approx 56/720 = 7.8%). Height 62%.

Good, responsive.

Now let's write it.

Also display computer-key mapping: on each key show the computer key (letter) as a badge, plus a legend list below with "A → C4 · W → C♯4 ...".

Note names with sharps: use "C♯4" label maybe just "C#4". Use "C♯4"? Keep "C#4" ASCII-safe? Both fine. I'll use "C♯4" for display... Safer ASCII: "C#4". I'll use ASCII.

Write the file now.

Wait — the `.key.black.active` uses `transform: translateY(2px)` but black keys are positioned with `transform: translateX(-50%)`. Conflict! The active transform would override translateX(-50%) and shift the key. Fix: use `left` calc without transform, or use `translate` property... Better: set black key left with `calc(...)` and margin-left negative? Use `transform: translateX(-50%)` on a wrapper? Simplest: set `el.style.left = ((n.afterWhite + 1) * WHITE_PCT - BLACK_WIDTH_PCT / 2) + '%'` and no transform. Then `.active` translateY works.

Let me fix that.

Also `e.target.closest` — for the keyboard div children (note/kbd spans), e.target may be the span; closest works on Elements. Fine.

Also pointerleave on window: fires when pointer leaves window — releasing all might be aggressive but acceptable? Hmm, if the user moves pointer out while holding a mouse button... Actually pointerleave on window fires whenever the mouse leaves the viewport even without pressing — releasing all is fine since nothing held. But wait — if the user is holding a computer key (keyboard sustain) and moves the mouse out of the window, releaseAll would kill the keyboard-held note. Edge case; but requirement says release held voices when window loses focus. pointerleave is a bit extra but ok. However there's a subtle problem: pointerleave on window fires for touch too? For touch, after pointerdown... pointercancel/pointerup handles. Hmm, but pointerleave can fire after a touch lift? Anyway.

Actually consider: keyboard key held (kbd source) + mouse moves out of window → pointerleave → releaseAll() kills keyboard note even though key still held. That would leave pressedCodes entry but no held note... then keyup -> noteOff does nothing (no sources). So no stuck note but note stops early. Minor. To be safer, make pointerleave only release pointer sources. But then which pointerIds? Track active pointer sources in a set. Let me track `activePointers` set of 'ptr:'+id added on pointerdown, removed on release. Simpler: releaseAllPointerSources: iterate held and remove sources starting with 'ptr:'. Let me implement that.

Actually simpler: on pointerleave, only release if there is any held pointer source... just release all pointer-sourced notes:

function releasePointers() { Object.keys(held).forEach(function(note){ Array.from(held[note]).forEach(function(s){ if (s.indexOf('ptr:')===0) noteOff(note,s); }); }); }

Use that for pointerleave too.

Now fix black key transform.

Also check `new Tone.PolySynth(Tone.Synth, {...})` — in v14.8, PolySynth constructor: (voiceConstructor, options). Options are passed to voice. Setting `synth.maxPolyphony = 12` works (setter). Good.

Also `Tone.Limiter` exists in v14.8. `Tone.Filter({frequency, type, rolloff})` fine.

Let me apply the edits.

Wait, I added a second 'blur' listener which is redundant (the earlier blur releases all). That's harmless but pointless. Actually the second blur listener calling releasePointerSources is redundant given releaseAll on blur. Let me remove that duplicate line — keep just pointerleave.

Actually it's harmless but sloppy. Let me clean it.

Also `.key.black.active` had `transform: translateY(2px)` — now works since black keys have no transform. Good.

Now run in browser.

Wait, my regex `/<script>\n([\s\S]*?)<\/script>/` matched the inline script (the second script tag). It replaced document/window/Tone with ({}) — but that would break syntax like `document.getElementById` -> `({}).getElementById` fine. Anyway it parsed.

Now browser test.

No curl. Browser tool likely loads index.html directly (file://) or via its own server. Let's just use the browser tool with reload. But tone.min.js is loaded via relative script src — browser tool should handle file loading.

Let me try browser inspect/reload.

Page loads, Tone.js v14.8.49 loaded, notes rendered. There's a CSP error about worker from blob — Tone.js uses a worker for something? In Tone v14, `Tone.Offline`/`Tone.getContext`? Actually the "worker-src 'none'" CSP blocks Tone's use of a `Worker` (probably for the `Tone.Loop`/Clock? Actually Tone v14 doesn't use workers... Hmm, maybe from `Tone.Offline` or from `standardized-audio-context`? It's blocked but Tone still works. This may affect `Tone.Reverb` impulse generation? We don't use reverb. Note it appears before user gesture — that's from Tone loading. It's a warning-level error but probably fine; audio context still works after gesture.

Wait — the worker blob error could be from `Tone.GrainPlayer`? Or from `tslib`... Let me not worry unless audio fails.

Click "Enable audio & start".

Audio running, console clean apart from the pre-existing Tone worker CSP notice (that occurs on Tone load — likely Tone's use of a worker for... hmm, actually it could be from `Tone.Offline` or from `standardized-audio-context`'s `AudioWorkletNode` support detection). Since PolySynth works with state "running", it's fine.

Wait — one thing: black keys are positioned correctly? Looking at the image: black keys appear at C#4 (between C4 and D4) ✓, D#4 ✓, then gap between E4-F4 ✓, F#4 ✓, G#4 ✓, A#4 ✓, gap between B4-C5 ✓. Good.

Hmm, but the black key labels appear at the bottom of black keys — visible. Good.

Now test keyboard input: press 'a' (KeyA → C4). The browser tool's `key` action — let's use it. Test keydown highlight, then keyup. Also test three simultaneous notes and mouse press/release outside key.

Let me press key 'a' and inspect/screenshot for highlight.

The screenshot was captured after keyup (the `key` action probably does press+release then screenshot). "Held notes: 0" — so the highlight was transient. To observe hold behavior I need to inspect mid-press. The browser tool may not support keydown-only. Alternative: use `type` action? That also completes. Better: verify state programmatically via `inspect` — but inspect gives DOM snapshot at a moment. Hmm.

Alternative approach: dispatch synthetic events via evaluate? The `inspect` action likely runs JS? Let me check what inspect returns — probably DOM/console. There may be no evaluate tool. I can verify the press/release logic by dispatching synthetic keydown events... but I can't run arbitrary JS unless there's a way.

Actually, I could temporarily instrument: add a visible "last event" log? Simpler: verify via DOM by using pointer drag — mouse down on a key then... `drag` action does press-move-release, screenshot after release.

Hmm. The screenshot after `key` shows "Held notes: 0", which is consistent with correct press-then-release (no stuck note). To verify highlight while held, I can create a quick test harness: use the `browser` `type` action with a long string? Still sequential.

Alternative: I can make a temporary test page? No — must test index.html.

Another way: use CSS to check `.active` class applied. I could add a temporary debug element that records history of held counts (e.g., a log list). Instead of temporary hacks, I can add a small permanent feature: nothing required. But verifying behavior matters.

Option: the `key` action might support keydown-only if text is like "a:down"? Unknown.

Better: use `browser` `type` into an input? No input exists.

Practical approach: temporarily instrument index.html with a debug overlay that records events (press/release) into the DOM, run the key action, and read the DOM log via `inspect`/screenshot. Then remove instrumentation. But simpler: keep a permanent, harmless event log in the DOM? Not needed in the final product but harmless... Better to do the temporary instrumentation and then remove.

Actually even better: the DOM snapshot shows "Held notes: N". If I could screenshot during hold... The `key` action seems to do down+up then screenshot. What about `browser.click` on a key with hold? `drag` from key to key — during drag, screenshot? Probably after.

Let me do the temporary instrumentation approach: append to a `#debugLog` element on noteOn/noteOff with e.g. "on C4 src kbd:KeyA | held=C4", plus the class state. Then run `key a` and inspect the DOM log to confirm attack was triggered and released. Also I can verify polyphony by pressing keys a, s, d in one `type` call? The `type` action types a string sequentially — each key down/up. Not simultaneous.

To verify 3 simultaneous notes, I can dispatch synthetic keyboard events from within the page... can't run JS directly. But I could add a hidden "test" hook — hmm.

Alternative: use pointer drag! `drag` from key1 to key3 while pressed: my implementation doesn't do glissando (pointerdown only on the initial key). But pointer drag from one key across others: only the first key gets pointerdown. So drag tests release-outside-key.

I could support multi-touch? Not testable via browser tool.

OK, temporary instrumentation plan:
1. Add debug logging into the page temporarily (window-level, appended to a visible `<pre id="dbg">`).
2. Also temporarily add a test that dispatches keydown events for A, S, D simultaneously? Actually I *can* dispatch synthetic events from an event handler triggered by a click — e.g., temporarily wire the "Enable audio" flow... no, the gate is hidden.

Simplest: temporarily modify the `startBtn` handler? It's already clicked. Hmm, I could temporarily add a test button "self-test" in the page that dispatches KeyboardEvents for KeyA/KeyS/KeyD keydown (held), then after 300ms checks `held` count and active classes, then keyups, and writes results into the debug panel. That's a legit temporary test harness. Synthetic KeyboardEvents are trusted=false but my handlers don't check isTrusted — they'll work.

Then inspect DOM results. Then remove the harness and re-verify final file loads clean.

Let's do it with a temporary edit, run, inspect, then revert. Actually, I can do it more cheaply: write a temporary copy test.html that includes index.html in an iframe? Sandbox restrictions... Just edit index.html temporarily.

Let me add a debug panel + self-test button quickly.

Actually — wait. Let me reconsider: maybe I don't need synthetic events for simultaneity. I can verify simultaneous notes via two pointers? No.

I'll do the temporary harness. Keep it small.

Plan for temporary code appended near end of script:

```js
// TEMP TEST HARNESS
var dbg = document.createElement('pre'); dbg.id='dbg'; dbg.style.cssText='white-space:pre-wrap;background:#000;color:#0f0;font:11px monospace;max-width:90vw';
document.body.appendChild(dbg);
function log(){ dbg.textContent += Array.prototype.join.call(arguments,' ') + '\n'; }
window.addEventListener('keydown', e=>log('EV keydown', e.code, 'repeat='+e.repeat));
window.addEventListener('keyup', e=>log('EV keyup', e.code));
var t = document.createElement('button'); t.textContent='selftest'; t.id='selftest';
t.onclick = function(){
  ['KeyA','KeyS','KeyD'].forEach(c=>window.dispatchEvent(new KeyboardEvent('keydown',{code:c})));
  log('after 3 keydowns: heldCount=', document.getElementById('heldCount').textContent,
      'activeKeys=', document.querySelectorAll('.key.active').length,
      'activeClasses=', Array.from(document.querySelectorAll('.key.active')).map(k=>k.dataset.note).join(','));
  // duplicate auto-repeat
  window.dispatchEvent(new KeyboardEvent('keydown',{code:'KeyA', repeat:true}));
  window.dispatchEvent(new KeyboardEvent('keydown',{code:'KeyA'}));
  log('after repeat events: heldCount=', document.getElementById('heldCount').textContent, 'activeKeys=', document.querySelectorAll('.key.active').length);
  ['KeyA','KeyS'].forEach(c=>window.dispatchEvent(new KeyboardEvent('keyup',{code:c})));
  log('after 2 keyups: heldCount=', document.getElementById('heldCount').textContent, 'active=', Array.from(document.querySelectorAll('.key.active')).map(k=>k.dataset.note).join(','));
  window.dispatchEvent(new KeyboardEvent('keyup',{code:'KeyD'}));
  log('after all keyups: heldCount=', document.getElementById('heldCount').textContent);
  window.dispatchEvent(new Event('blur'));
  log('after blur: heldCount=', document.getElementById('heldCount').textContent);
};
document.body.appendChild(t);
```

Also pointer test: simulate pointerdown on a key element then pointerup outside: dispatch PointerEvent on key el with pointerId 7, then window pointerup with pointerId 99 (different) → should stay held; then window pointerup pointerId 7 → released. Log results. Good — tests "release when pointer released outside a key" (window pointerup handler).

Then click 'selftest' button via browser click, then inspect.

Let me implement.

Note: `keyEls` is defined inside the IIFE, and my harness is inside the IIFE too (appended before `})();`). Yes, I replaced the console.log line which is inside the IIFE just before its end. Good.

Also PointerEvent constructor support: Chrome supports it. The harness's `blur` event dispatch on window: `new Event('blur')` dispatched to window works.

Run: reload, click start button (gate), then click SELFTEST, then inspect DOM.

Harness present. Now click "Enable audio & start" (597,468), then click SELFTEST (50,25).

Audio running. The debug panel is at bottom-left but seemingly empty/black (it's black with green text; content maybe empty since no logs yet). Now click SELFTEST (50, 25).

All 8 checks pass:
1) 3 simultaneous notes held & highlighted (C4,D4,E4) ✓
2) auto-repeat does not duplicate ✓ (heldCount stays 3)
3) partial release ✓
4) full release ✓
5) pointerdown highlights ✓
6) foreign pointerup doesn't release ✓ (good, that's a different pointer)
7) pointerup outside key releases ✓
8) window blur releases ✓

Also visible: keys highlight while held (screenshot at end shows none since released). Note test 3 confirmed highlight state.

Now do one real mouse press/hold test? The browser click is instantaneous. I could do a real drag to verify pointerdown highlight visually... but the highlight class check above already covers that with real event dispatch through handlers. Also earlier real keyboard `a` press worked without stuck notes.

Let me also visually verify highlight during hold using a real interaction: press mouse down on a key and screenshot before release — the `drag` action may capture mid? Probably not. Alternative: I already verified class toggling. But a visual check of highlight styling would be nice: I can temporarily force `.active` class via... can't run JS. Hmm — but the selftest could add: after step 5, hold and screenshot? The screenshot happens after click returns (after all steps). I could make the harness pause: hold notes and not release, then screenshot shows highlighted keys, then a second button to release. Let me do a quick visual: add a second test button "HOLD" that presses A,S,D and leaves them held. Click it, screenshot → see highlighted keys visually. Then click "SELFTEST" (step 4 releases all? it ends with blur releasing). Actually clicking SELFTEST again would run steps and end released. Good.

Let me add a HOLD button quickly... Actually simpler: modify the existing harness? Cheaper: just add a second button in the same temp block. But is it worth the time? It validates visual highlight appearance (a stated requirement: "Highlight keys while held"). Yes, quick.

Alternatively, use browser `drag` with toX/toY — if drag keeps mouse down during... screenshot happens after mouse up. Hmm.

I'll add the HOLD button via edit. Actually, I can just click SELFTEST-like: I'll add it minimally.

Also should test real pointer press highlight through real mouse: use `click` on a key → instant. Fine.

Let me add: a button "HOLD3" that dispatches pointerdown+keydown for 3 notes and leaves them held. Then screenshot. Then click SELFTEST to clear (its step 1 adds 3 keydowns of A,S,D — but they may already be held... it would add same source ids 'kbd:KeyA' etc. - held set already contains them; step1 logs heldCount=3 then steps release... final blur releases all). OK.

Implement HOLD3.

Wait: `document.body.appendChild(t);` appears twice? No — only once in my harness (I wrote `document.body.appendChild(t);` at the end of harness). Let me check: in the harness I have `document.body.appendChild(dbg);` and `document.body.appendChild(t);`. The edit oldText "document.body.appendChild(t);" is unique. It succeeded. Good.

Reload and click HOLD3 at (120+~40, 25)≈ (155,25). Need to re-enable audio? Highlight works without audio anyway. Reload → click start → click HOLD3 → screenshot.

Click HOLD3 at (151,25). Then screenshot to see highlighted keys (C4 white, C#4 black, G4 white). Audio gate is still up but that's fine visually — actually the gate overlay covers with blur, making the keyboard hard to see. So first click "Enable audio & start" (597,468), then HOLD3.

Now click HOLD3 at (151,25) — this click itself is a real mouse press/release, then the button leaves notes held. Screenshot will show highlighted keys.

Note: clicking HOLD3 also dispatches 'pointerup' on window after — releaseAll('ptr:...) for the click's pointerId, which is fine (button click source isn't tracked). Good.

Highlight visual confirmed: C4 white key blue, C#4 black key purple, G4 white key blue; legend items lit; "Held notes: 3".

Now: release them (click SELFTEST or real keyup) and then remove the test harness from the file, reload and verify the final file is clean.

Also one more real-interaction check with the final file: press real keys after enabling audio, check console no errors. Earlier I did `key a` — no errors.

Let me remove the harness now.

No python3. Use node or sed. Let me use node.

My python-style cut removed too much: I cut from '/* TEMP TEST HARNESS */' to the first occurrence of '  })();' after it — but the IIFE's closing is '  })();' at2-space indent... the harness was inside the IIFE right before its closing. Wait — the harness end should be immediately followed by '  })();' which is the IIFE close. But cutting to `s.indexOf('  })();', start)` removed the harness AND kept the `  })();`. Hmm, then why syntax error at line 259 `})`?

Oh! Inside the harness there was `t.addEventListener('click', function () { ... });` and my search for '  })();' — the harness contains `      });` etc, not '  })();'. Hmm. But the debug panel function used `document.body.appendChild(h);` ... Let me look at the actual current file around line 240-260 to see what happened.

Actually the issue: the harness code was placed after the console.log line but the console.log line is inside the IIFE at indentation 4: "    console.log('[piano] Ready...')". After the harness, the file continues with '  })();' which closes the IIFE. My slice kept everything from '  })();' onward. That should be fine...

Unless: `s.indexOf('  })();', start)` found an earlier occurrence... within the harness? The harness has `function log() { dbg.textContent += ... }` — no. Hmm, wait: `heldInfo()` ends with `}` ... `t.addEventListener('click', function () {...});` — the inner content has `});` lines at 8-space indentation. There's no '  })();' inside.

Hmm, but maybe the earlier console.log replacement... Let me just look at the file.

I see — the file order: the harness was at the END of the IIFE (after the console.log 'Ready' line). But wait — the current file shows the console.log 'Ready' line at 541 followed by two `})();`. My slice removed from '/* TEMP TEST HARNESS */' to the '  })();' — but apparently the harness block appeared BEFORE the console.log 'Ready'?? No...

Hmm, look: line 541 has 'Ready' log then blank, then `})();` twice. It seems the cut removed from '/* TEMP TEST HARNESS */' up to and including... wait my slice kept `s.slice(end)` which starts with '  })();' — so the harness text is gone and there are two '})();' lines: one was part of the original end of the IIFE (kept by slice) and one extra?

Ah I see — the `edit` I used to insert the harness replaced the 'Ready' console.log line with 'Ready log + harness' — so the harness came after the Ready log. Then the harness ended with `})();`? No... my inserted harness code ended with `})();` for its own IIFE `(function(){...})()`! Yes — I wrote `/* TEMP TEST HARNESS */\n    (function () { ... })();`? Let me check: I wrote:

```
    /* TEMP TEST HARNESS */
    (function () {
      ...
 document.body.appendChild(t);
    })();
```

Hmm, did I close it with `})();`? Looking at my edit newText: it ends with `document.body.appendChild(h);` and earlier `})();`? Let me recall... The newText ended with:

```
      document.body.appendChild(h);
```

and before that within, the harness started with `(function () {`? Actually I wrote `/* TEMP TEST HARNESS */\n    (function () {\n      var dbg = ...` and I ended with `})();`? The last lines were:

```
      document.body.appendChild(h);
```
followed by nothing — no `})();`. Hmm, but the original console.log line was the last line before `})();` (the main IIFE close). So the harness `(function () {` was never closed! That explains: my cut to the first '  })();' found the main IIFE close, leaving... but now there are two `})();` at 543-544.

Wait, the current state after my node cut: line 543 `})();` and 544 `})();`. The slice removed from start ('/* TEMP TEST HARNESS */') to the index of '  })();' after start — that '  })();' occurrence... Since the harness itself lacked a closing, the only '  })();' after start would be... hmm, but there were TWO. Because the harness's `heldInfo` etc...Whatever the exact cause, current file has a stray extra `})();` at line 544 and the main IIFE closes at 543. Actually the main IIFE opens with `(function () {` at line ~200 and closes at 543 with `})();`, then 544 has an extra `})();` that's a syntax error.

Fix: remove line 544 (the second `})();`). Then verify parse.

Wait — but if the harness `(function () {` was unclosed and the cut removed everything from '/* TEMP TEST HARNESS */' to the first '  })();'... then the harness body was removed along with... hmm, but where did the harness `(function () {` go? It was at start — removed. And the cut removed everything up to and including? `s.slice(end)` keeps the '  })();'. So we lost the harness body and one '})();'. But then the leftover extra `})();`... 

Let me just verify: check the tail of file, and confirm no leftover harness code, and the whole thing parses.

The file is clean and parses. Do one final browser reload + quick interaction check (enable audio, press a key), then report. Keep it quick.

Clean load: no harness, labels + mapping correct. The CSP worker error comes from Tone.js loading itself (unrelated to my code) and the autoplay warnings are pre-gesture — expected.

Final: click enable audio (597,468), then play real keys 'a','w','k' via key actions and check console for errors. One combined check: click start, then press key 'a' and 'k'. Keep to 2 steps.

Final quick check: play a real key and a mouse click on a key to confirm no console errors and no stuck state. One more browser call with `key` text "ak" — plays two notes. Then done.

The key action takes one key. I already tested key 'a' earlier (worked). Let me do one mouse click on a key to confirm pointer path works without errors, then finish. Click on E4 white key at (445, 300).

Mouse click on E4 produced no console errors and left "Held notes: 0" (correct press + release). Everything verified. File is saved at /tmp/job-3xDdkd/index.html. Report.