diff --git a/demo/benchmark_led_strips.mjs b/demo/benchmark_led_strips.mjs
index a14d9a82..8e2a8446 100644
--- a/demo/benchmark_led_strips.mjs
+++ b/demo/benchmark_led_strips.mjs
@@ -8,17 +8,33 @@
  * (50 strips × 50 points); `--size=none` is the same build and plan without
  * strips. No icon is added: the converted devices keep their ids, only their
  * entity becomes a light. Light radius 50 cm (the strip default), Glow on,
- * viewport 1440×1000, DPR 1, reduced motion. Every sample is cold: a new
- * browser with an empty cache mounts a new card.
+ * viewport 1440×1000, DPR 1, reduced motion. `--warmups` (≥1) samples are
+ * discarded, then `--samples` (≥7) are judged. Every sample is cold: a new
+ * browser with an empty cache mounts a new card; the warm metrics run in the
+ * same page after the module has loaded.
  *
- * Metrics (judged on median and p95 against budgets-led-strips.json):
- * firstStableRenderMs (mount → stripes and fields of every visible strip),
- * warmSpaceReadyMs (space switch with the module loaded → stable LED frame),
- * stateUpdateMs (all strip sources switched → every stripe in its new state),
- * panZoomMs and its longest Long Task, retained heap after 20 A→B→C→A cycles.
- * Counters (must be exact): field geometry recomputes over 100 unrelated HA
- * ticks, 100 pan/zoom steps and a colour-only change (0), cache entries ≤ 50
- * and equal after every cycle, LED chunk requests (none without strips).
+ * Metrics (judged on median AND p95 against budgets-led-strips.json):
+ * firstStableRenderMs (mount → stripes and fields of every visible strip,
+ * cold import included), warmSpaceReadyMs (space switch with the module
+ * loaded → stable LED frame), stateUpdateMs (the interaction profile's method:
+ * hass update → every stripe in its new state), panZoomMs (the interaction
+ * profile's camera scenario, benchmark_large_house.mjs) and the longest Long
+ * Task of the camera — the scenario and the 100-step series, retained heap
+ * after 20 A→B→C→A cycles over a warm cycle (same GC protocol).
+ *
+ * Counters (exact, every sample): geometry/visibility recomputes over 100
+ * unrelated HA ticks, 100 pan/zoom steps and a colour-only change (0); the
+ * three LED caches of the shown space — shapes ≤ 50, visibility ≤ 50,
+ * retained per-emitter fans ≤ 2500 — identical after every cycle (growth 0);
+ * after disconnect 0 retained entries and 0 live LED timers/observers; a
+ * late import after disconnect restores nothing (one extra cold run with the
+ * runtime response delayed); LED chunk requests (none without strips, never
+ * the editor chunk in the View).
+ *
+ * `--merge=a.json,b.json` judges the rows of several partial reports of the
+ * same size as one run — the samples are the same cold samples, only the
+ * process that collected them differs (a runner with a short step limit);
+ * `--warmup-only` collects the discarded warm-up of such a run.
  */
 import { execFileSync } from 'node:child_process';
 import { mkdirSync, readFileSync, writeFileSync } from 'node:fs';
@@ -27,15 +43,19 @@ import { launch } from './serve.mjs';
 import { makeLedStripsFixture } from './performance/led-strips-fixture.mjs';
 
 const valueArg = (name) => process.argv.find((arg) => arg.startsWith(`--${name}=`))?.slice(name.length + 3);
-const samples = Math.max(1, Math.min(20, Number(valueArg('samples')) || 7));
-const warmups = Math.max(0, Math.min(5, Number(valueArg('warmups')) || 1));
+const warmupOnly = process.argv.includes('--warmup-only');
+const samples = warmupOnly ? 0 : Math.max(1, Math.min(20, Number(valueArg('samples')) || 7));
+const warmups = warmupOnly ? 1 : Math.max(0, Math.min(5, Number(valueArg('warmups') ?? 1)));
 const size = valueArg('size') ?? '10x5';
 const output = valueArg('output') ? resolve(valueArg('output')) : null;
+const merge = valueArg('merge')?.split(',').filter(Boolean).map((file) => resolve(file)) ?? null;
+const skipLateImport = process.argv.includes('--no-late-import');
 const SIZES = { '10x5': [10, 5], '50x50': [50, 50], none: [0, 0] };
 if (!SIZES[size]) throw new Error(`unknown size: ${size}`);
 const [STRIPS, POINTS] = SIZES[size];
 const PROFILE = 'led-strips-v1';
 const CYCLES = Math.max(1, Math.min(20, Number(valueArg('cycles')) || 20));
+const MIN_SAMPLES = 7;
 
 const fixture = makeLedStripsFixture(STRIPS, POINTS);
 const sourceSha = (() => {
@@ -43,43 +63,59 @@ const sourceSha = (() => {
 })();
 const budgets = JSON.parse(readFileSync(new URL('./performance/budgets-led-strips.json', import.meta.url), 'utf8'));
 
-const rows = [];
-let chromium = null;
-for (let iteration = 0; iteration < warmups + samples; iteration++) {
-  const { page, browser } = await launch({ width: 1440, height: 1000 }, 1,
-    ['--enable-precise-memory-info', '--js-flags=--expose-gc']);
-  chromium ??= await browser.version();
-  await page.emulateMedia({ reducedMotion: 'reduce' });
-  const requests = [];
-  page.on('request', (request) => {
-    const name = request.url().replace(/.*\//, '').replace(/\?.*$/, '');
-    if (/^led-strip-(runtime|field|editor)-/.test(name)) requests.push(name.replace(/-[^-]+\.js$/, ''));
-  });
-  try {
-    const row = await page.evaluate(async ({ fixture, strips, cycles }) => {
-      const frame = () => new Promise((done) => requestAnimationFrame(() => requestAnimationFrame(done)));
-      const sleep = (ms) => new Promise((done) => setTimeout(done, ms));
-      const until = async (predicate, timeout = 20000) => {
-        const started = performance.now();
-        while (!predicate()) {
-          if (performance.now() - started > timeout) throw new Error('led-strips-v1 timed out');
-          await sleep(5);
-        }
-      };
-      const longTasks = () => {
-        const entries = [];
-        const observer = new PerformanceObserver((list) => entries.push(...list.getEntries()));
-        observer.observe({ type: 'longtask', buffered: false });
-        return async () => {
-          await sleep(0);
-          entries.push(...observer.takeRecords());
-          observer.disconnect();
-          return Number(Math.max(0, ...entries.map((entry) => entry.duration)).toFixed(2));
-        };
-      };
-      const gc = async () => { if (globalThis.gc) { globalThis.gc(); await frame(); globalThis.gc(); await frame(); } };
-      window.__card?.remove?.();
-      localStorage.clear();
+/**
+ * Installed in the page before the card mounts anything: timers, frames and
+ * observers created from an LED chunk (its file name is in the creation
+ * stack) are tracked until they fire, are cleared or disconnected.
+ */
+function installLedLifecycleTracker() {
+  if (window.__ledLive) return;
+  const live = { timers: new Set(), frames: new Set(), observers: new Set() };
+  window.__ledLive = live;
+  const fromLed = () => /led-strip-/.test(new Error().stack || '');
+  const nativeTimeout = window.setTimeout, nativeClearTimeout = window.clearTimeout;
+  window.setTimeout = function setTimeout(fn, ms, ...rest) {
+    const mine = fromLed();
+    let id = 0;
+    id = nativeTimeout.call(window, typeof fn === 'function'
+      ? (...args) => { live.timers.delete(id); return fn(...args); } : fn, ms, ...rest);
+    if (mine) live.timers.add(id);
+    return id;
+  };
+  window.clearTimeout = function clearTimeout(id) { live.timers.delete(id); return nativeClearTimeout.call(window, id); };
+  const nativeInterval = window.setInterval, nativeClearInterval = window.clearInterval;
+  window.setInterval = function setInterval(fn, ms, ...rest) {
+    const id = nativeInterval.call(window, fn, ms, ...rest);
+    if (fromLed()) live.timers.add(id);
+    return id;
+  };
+  window.clearInterval = function clearInterval(id) { live.timers.delete(id); return nativeClearInterval.call(window, id); };
+  const nativeFrame = window.requestAnimationFrame, nativeCancelFrame = window.cancelAnimationFrame;
+  window.requestAnimationFrame = function requestAnimationFrame(fn) {
+    const mine = fromLed();
+    let id = 0;
+    id = nativeFrame.call(window, (time) => { live.frames.delete(id); return fn(time); });
+    if (mine) live.frames.add(id);
+    return id;
+  };
+  window.cancelAnimationFrame = function cancelAnimationFrame(id) { live.frames.delete(id); return nativeCancelFrame.call(window, id); };
+  for (const name of ['ResizeObserver', 'MutationObserver', 'IntersectionObserver']) {
+    const Native = window[name];
+    if (!Native) continue;
+    window[name] = class extends Native {
+      constructor(callback) {
+        super(callback);
+        if (fromLed()) live.observers.add(this);
+      }
+      disconnect() { live.observers.delete(this); return super.disconnect(); }
+    };
+  }
+}
+
+/** The page side of one mount: the same fixture host as before, shared by the sample and the late-import run. */
+function pageHost() {
+  return `
+    window.__ledHost = (fixture) => {
       const card = document.createElement('houseplan-card');
       card.setConfig({ type: 'custom:houseplan-card', title: 'LED strips', icon_size: 3.4 });
       let states = fixture.states;
@@ -100,19 +136,74 @@ for (let iteration = 0; iteration < warmups + samples; iteration++) {
         formatEntityState: (state) => state.state,
         config: { unit_system: { length: 'km' } },
       };
-      const setStates = (next) => { states = next; card.hass = { ...hassBase, states }; };
+      return {
+        card,
+        get states() { return states; },
+        setStates(next) { states = next; card.hass = { ...hassBase, states }; },
+      };
+    };
+    window.__ledStats = async (card) => {
+      const url = performance.getEntriesByType('resource').map((entry) => entry.name)
+        .find((name) => /led-strip-runtime-[^/]+\\.js/.test(name));
+      if (!url) return { shapes: 0, visibility: 0, sources: 0, recomputes: 0, loaded: false };
+      const runtime = await import(url);
+      return { ...runtime.ledStats(card), loaded: true };
+    };
+    window.__ledLiveCounts = () => ({
+      timers: window.__ledLive.timers.size, frames: window.__ledLive.frames.size,
+      observers: window.__ledLive.observers.size,
+    });
+  `;
+}
+
+async function sample() {
+  const { page, browser } = await launch({ width: 1440, height: 1000 }, 1,
+    ['--enable-precise-memory-info', '--js-flags=--expose-gc']);
+  const chromium = await browser.version();
+  await page.emulateMedia({ reducedMotion: 'reduce' });
+  const requests = [];
+  page.on('request', (request) => {
+    const name = request.url().replace(/.*\//, '').replace(/\?.*$/, '');
+    if (/^led-strip-(runtime|field|editor)-/.test(name)) requests.push(name.replace(/-[^-]+\.js$/, ''));
+  });
+  try {
+    await page.evaluate(installLedLifecycleTracker);
+    await page.evaluate(pageHost());
+    const row = await page.evaluate(async ({ fixture, strips, cycles }) => {
+      const frame = () => new Promise((done) => requestAnimationFrame(() => requestAnimationFrame(done)));
+      const sleep = (ms) => new Promise((done) => setTimeout(done, ms));
+      const until = async (predicate, timeout = 30000) => {
+        const started = performance.now();
+        while (!predicate()) {
+          if (performance.now() - started > timeout) throw new Error('led-strips-v1 timed out');
+          await sleep(5);
+        }
+      };
+      const longTasks = () => {
+        const entries = [];
+        const observer = new PerformanceObserver((list) => entries.push(...list.getEntries()));
+        observer.observe({ type: 'longtask', buffered: false });
+        return async () => {
+          await sleep(0);
+          entries.push(...observer.takeRecords());
+          observer.disconnect();
+          return Number(Math.max(0, ...entries.map((entry) => entry.duration)).toFixed(2));
+        };
+      };
+      const gc = async () => { if (globalThis.gc) { globalThis.gc(); await frame(); globalThis.gc(); await frame(); } };
+      window.__card?.remove?.();
+      localStorage.clear();
+      const host = window.__ledHost(fixture);
+      const { card } = host;
       const root = () => card.renderRoot;
       const count = (selector) => root()?.querySelectorAll(selector).length ?? 0;
       const ledStable = (state = 'on') => count(`[data-led-strip][data-state="${state}"]`) === strips
         && (state !== 'on' || count('.led-fields [data-led-field]') === strips);
-      const cache = () => {
-        const group = root().querySelector('.led-fields');
-        return group ? { size: Number(group.dataset.ledCache), recomputes: Number(group.dataset.ledRecomputes) } : null;
-      };
+      const stats = () => window.__ledStats(card);
 
       const started = performance.now();
       document.getElementById('host').replaceChildren(card);
-      setStates(states);
+      host.setStates(host.states);
       await until(() => card._loadOk && card._model?.length === 3);
       if (strips) await until(() => ledStable());
       else { await until(() => card._booting === false); await frame(); }
@@ -126,28 +217,31 @@ for (let iteration = 0; iteration < warmups + samples; iteration++) {
       await frame();
       const warmSpaceReadyMs = Number((performance.now() - warm).toFixed(2));
 
+      const states = host.states;
       const floorLights = Object.keys(states).filter((id) => id.startsWith('light.perf_led_1_'));
       const stateStarted = performance.now();
-      setStates({ ...states, ...Object.fromEntries(floorLights.map((id) => [id, { ...states[id], state: 'off' }])) });
+      host.setStates({ ...states, ...Object.fromEntries(floorLights.map((id) => [id, { ...states[id], state: 'off' }])) });
       await card.updateComplete;
       if (strips) await until(() => ledStable('off'));
       await frame();
       const stateUpdateMs = Number((performance.now() - stateStarted).toFixed(2));
-      setStates({ ...states, ...Object.fromEntries(floorLights.map((id) => [id, { ...states[id], state: 'on' }])) });
+      host.setStates({ ...states, ...Object.fromEntries(floorLights.map((id) => [id, { ...states[id], state: 'on' }])) });
       await card.updateComplete;
       if (strips) await until(() => ledStable());
       await frame();
 
-      const before = strips ? cache() : null;
+      const before = await stats();
       // 100 unrelated HA ticks.
-      const sensor = Object.keys(states).find((id) => id.startsWith('sensor.'));
+      const sensor = Object.keys(host.states).find((id) => id.startsWith('sensor.'));
       for (let tick = 0; tick < 100; tick++) {
-        setStates({ ...states, [sensor]: { ...states[sensor], state: String(20 + (tick % 10) / 10) } });
+        host.setStates({ ...host.states, [sensor]: { ...host.states[sensor], state: String(20 + (tick % 10) / 10) } });
         await card.updateComplete;
       }
       await frame();
-      const afterTicks = strips ? cache() : null;
-      // Pan/zoom: the camera scenario, then 100 steps for the counter.
+      const afterTicks = await stats();
+      // The camera: the interaction profile's scenario (one wheel step, its
+      // render and frame — benchmark_large_house.mjs), then 100 steps whose
+      // Long Tasks are judged too and whose recomputes are counted.
       const stage = root().querySelector('.stage');
       const rect = stage.getBoundingClientRect();
       const wheel = (deltaY) => stage.dispatchEvent(new WheelEvent('wheel', {
@@ -160,21 +254,24 @@ for (let iteration = 0; iteration < warmups + samples; iteration++) {
       await frame();
       const panZoomMs = Number((performance.now() - panStarted).toFixed(2));
       const panZoomLongTaskMaxMs = await stopPan();
-      // 100 more camera steps for the counters only (not a timing window).
+      const stopSeries = longTasks();
+      // One wheel step per frame, as a real wheel or trackpad delivers them.
       for (let step = 0; step < 100; step++) {
         wheel(step % 2 ? 60 : -60);
         await card.updateComplete;
+        await frame();
       }
       await frame();
-      const afterCamera = strips ? cache() : null;
+      const cameraSeriesLongTaskMaxMs = await stopSeries();
+      const afterCamera = await stats();
       // A colour-only change rebuilds no geometry or visibility.
-      setStates({ ...states, ...Object.fromEntries(floorLights.map((id) => [id,
-        { ...states[id], attributes: { ...states[id].attributes, rgb_color: [255, 120, 80] } }])) });
+      host.setStates({ ...host.states, ...Object.fromEntries(floorLights.map((id) => [id,
+        { ...host.states[id], attributes: { ...host.states[id].attributes, rgb_color: [255, 120, 80] } }])) });
       await card.updateComplete;
       await frame();
-      const afterColour = strips ? cache() : null;
+      const afterColour = await stats();
 
-      // 20 cycles A→B→C→A after one warm cycle; cache size equal after each.
+      // 20 cycles A→B→C→A after one warm cycle; the three caches identical after each.
       const cycle = async () => {
         for (const id of ['perf-floor-1', 'perf-floor-2', 'perf-floor-3', 'perf-floor-1']) {
           card._pickSpace(id);
@@ -182,51 +279,149 @@ for (let iteration = 0; iteration < warmups + samples; iteration++) {
           if (strips) await until(() => ledStable());
         }
         await frame();
-        return strips ? cache().size : 0;
+        const { shapes, visibility, sources } = await stats();
+        return { shapes, visibility, sources };
       };
       await cycle();
       await gc();
       const heapBefore = performance.memory?.usedJSHeapSize ?? null;
-      const sizes = [];
-      for (let index = 0; index < cycles; index++) sizes.push(await cycle());
+      const cycleStats = [];
+      for (let index = 0; index < cycles; index++) cycleStats.push(await cycle());
       await gc();
       const heapAfter = performance.memory?.usedJSHeapSize ?? null;
+      const liveBeforeDisconnect = window.__ledLiveCounts();
       card.remove();
       await frame();
+      await sleep(600);
+      const afterDisconnect = await stats();
+      const liveAfterDisconnect = window.__ledLiveCounts();
+      const key = (entry) => `${entry.shapes}/${entry.visibility}/${entry.sources}`;
       return {
-        firstStableRenderMs, warmSpaceReadyMs, stateUpdateMs, panZoomMs, panZoomLongTaskMaxMs,
+        firstStableRenderMs, warmSpaceReadyMs, stateUpdateMs, panZoomMs, panZoomLongTaskMaxMs, cameraSeriesLongTaskMaxMs,
         retainedHeapBytes: heapBefore == null || heapAfter == null ? null : Math.max(0, heapAfter - heapBefore),
         counters: strips ? {
           recomputesOnHaTicks: afterTicks.recomputes - before.recomputes,
           recomputesOnCamera: afterCamera.recomputes - afterTicks.recomputes,
           recomputesOnColour: afterColour.recomputes - afterCamera.recomputes,
-          cacheEntries: Math.max(...sizes),
-          cacheGrowthOverCycles: Math.max(...sizes) - Math.min(...sizes),
+          shapes: Math.max(...cycleStats.map((entry) => entry.shapes)),
+          visibility: Math.max(...cycleStats.map((entry) => entry.visibility)),
+          sources: Math.max(...cycleStats.map((entry) => entry.sources)),
+          cacheGrowthOverCycles: new Set(cycleStats.map(key)).size - 1,
         } : null,
+        disconnect: {
+          retained: afterDisconnect.shapes + afterDisconnect.visibility + afterDisconnect.sources,
+          liveBefore: liveBeforeDisconnect,
+          live: liveAfterDisconnect.timers + liveAfterDisconnect.frames + liveAfterDisconnect.observers,
+        },
       };
     }, { fixture, strips: STRIPS, cycles: CYCLES });
     row.ledRequests = [...new Set(requests)].sort();
-    if (iteration >= warmups) rows.push(row);
+    return { row, chromium };
   } finally {
     await browser.close();
   }
 }
 
+/**
+ * The late import: the card is removed while the runtime chunk is still on
+ * the wire (its response is held back); when it lands nothing is rendered,
+ * cached or scheduled for the gone card.
+ */
+async function lateImport() {
+  const { page, browser } = await launch({ width: 1440, height: 1000 }, 1, []);
+  try {
+    let held = false;
+    let runtimeUrl = null;
+    await page.route(/led-strip-runtime-[^/]+\.js/, async (route) => {
+      held = true;
+      runtimeUrl = route.request().url();
+      await new Promise((done) => setTimeout(done, 1500));
+      await route.fallback();
+    });
+    await page.evaluate(installLedLifecycleTracker);
+    await page.evaluate(pageHost());
+    const result = await page.evaluate(async ({ fixture }) => {
+      const sleep = (ms) => new Promise((done) => setTimeout(done, ms));
+      window.__card?.remove?.();
+      const host = window.__ledHost(fixture);
+      const { card } = host;
+      document.getElementById('host').replaceChildren(card);
+      host.setStates(host.states);
+      const started = performance.now();
+      while (!(card._loadOk && card._model?.length === 3) && performance.now() - started < 20000) await sleep(10);
+      await sleep(300);
+      const before = card.renderRoot.querySelectorAll('[data-led-strip]').length;
+      card.remove();
+      window.__lateCard = card;
+      await sleep(3000);
+      return { stripesBeforeLoad: before, stripesAfterLoad: card.renderRoot.querySelectorAll('[data-led-strip]').length };
+    }, { fixture });
+    // The chunk the card asked for, by its URL: the same module instance.
+    const late = await page.evaluate(async (url) => {
+      const runtime = url ? await import(url) : null;
+      return { stats: runtime ? { ...runtime.ledStats(window.__lateCard), loaded: true } : { shapes: 0, visibility: 0, sources: 0, loaded: false },
+        live: window.__ledLiveCounts() };
+    }, runtimeUrl);
+    return { ...result, ...late, held };
+  } finally {
+    await browser.close();
+  }
+}
+
+let rows = [];
+let chromium = null;
+let late = null;
+let discarded = 0;
+if (merge) {
+  for (const file of merge) {
+    const part = JSON.parse(readFileSync(file, 'utf8'));
+    if (part.profile !== PROFILE || part.size !== size) throw new Error(`${file} is not ${PROFILE} ${size}`);
+    rows.push(...part.rows);
+    discarded += part.warmups;
+    chromium ??= part.chromium;
+    late ??= part.lateImport ?? null;
+  }
+} else {
+  for (let iteration = 0; iteration < warmups + samples; iteration++) {
+    const result = await sample();
+    chromium ??= result.chromium;
+    if (iteration >= warmups) rows.push(result.row);
+  }
+  discarded = warmups;
+  if (STRIPS && !skipLateImport && !warmupOnly) late = await lateImport();
+}
+if (warmupOnly) {
+  // A discarded warm-up sample for a later --merge: nothing is judged here.
+  const text = `${JSON.stringify({ profile: PROFILE, size, sourceSha, chromium, samples: 0, warmups: 1, rows: [], partial: true }, null, 2)}\n`;
+  if (output) { mkdirSync(dirname(output), { recursive: true }); writeFileSync(output, text); }
+  console.log(text);
+  process.exit(0);
+}
+
 const metric = (name) => {
   const values = rows.map((row) => row[name]).filter((value) => Number.isFinite(value)).sort((a, b) => a - b);
   const at = (q) => values[Math.min(values.length - 1, Math.ceil(q * values.length) - 1)];
   return { median: values.length ? at(0.5) : null, p95: values.length ? at(0.95) : null, samples: values };
 };
-const METRICS = ['firstStableRenderMs', 'warmSpaceReadyMs', 'stateUpdateMs', 'panZoomMs', 'panZoomLongTaskMaxMs', 'retainedHeapBytes'];
+const METRICS = ['firstStableRenderMs', 'warmSpaceReadyMs', 'stateUpdateMs', 'panZoomMs', 'panZoomLongTaskMaxMs',
+  'cameraSeriesLongTaskMaxMs', 'retainedHeapBytes'];
 const report = {
   profile: PROFILE, size, strips: STRIPS, points: POINTS, sourceSha, chromium,
-  samples, warmups, cycles: CYCLES, viewport: { width: 1440, height: 1000 }, dpr: 1,
+  samples: rows.length, warmups: discarded, cycles: CYCLES, viewport: { width: 1440, height: 1000 }, dpr: 1,
+  merged: merge ? merge.length : undefined,
   metrics: Object.fromEntries(METRICS.map((name) => [name, metric(name)])),
   counters: rows[0]?.counters ?? null,
   counterSamples: rows.map((row) => row.counters),
+  disconnectSamples: rows.map((row) => row.disconnect),
+  lateImport: late,
   ledRequests: [...new Set(rows.flatMap((row) => row.ledRequests))].sort(),
+  rows,
 };
 const failures = [];
+const partial = !merge && (samples < MIN_SAMPLES || warmups < 1);
+if (!partial && (report.samples < MIN_SAMPLES || report.warmups < 1)) {
+  failures.push(`${report.samples} samples after ${report.warmups} warmups: the profile needs ≥ ${MIN_SAMPLES} after ≥ 1`);
+}
 const limits = budgets.sizes[size] || {};
 for (const [name, limit] of Object.entries(limits)) {
   for (const stat of ['median', 'p95']) {
@@ -235,19 +430,34 @@ for (const [name, limit] of Object.entries(limits)) {
     if (value > limit) failures.push(`${name} ${stat} ${value} > ${limit}`);
   }
 }
+for (const [index, disconnect] of report.disconnectSamples.entries()) {
+  if (disconnect.retained !== 0) failures.push(`sample ${index}: ${disconnect.retained} LED cache entries retained after disconnect`);
+  if (disconnect.live !== 0) failures.push(`sample ${index}: ${disconnect.live} LED timers/frames/observers alive after disconnect`);
+}
 if (STRIPS) {
+  const caches = budgets.caches;
   for (const counters of report.counterSamples) {
     for (const key of ['recomputesOnHaTicks', 'recomputesOnCamera', 'recomputesOnColour', 'cacheGrowthOverCycles']) {
       if (counters[key] !== 0) failures.push(`${key} = ${counters[key]}, expected 0`);
     }
-    if (counters.cacheEntries > budgets.cacheEntries) failures.push(`cache entries ${counters.cacheEntries} > ${budgets.cacheEntries}`);
+    for (const key of ['shapes', 'visibility', 'sources']) {
+      if (counters[key] > caches[key]) failures.push(`${key} cache ${counters[key]} > ${caches[key]}`);
+    }
   }
+  if (late) {
+    if (!late.held || !late.stats.loaded) failures.push('late import: the runtime response was never held or never landed');
+    if (late.stripesAfterLoad !== late.stripesBeforeLoad) failures.push('late import rendered the gone card');
+    const retained = late.stats.shapes + late.stats.visibility + late.stats.sources;
+    if (retained) failures.push(`late import restored ${retained} cache entries`);
+    if (late.live.timers + late.live.frames + late.live.observers) failures.push('late import left LED timers/observers');
+  } else if (!skipLateImport) failures.push('late import not measured');
   if (!report.ledRequests.includes('led-strip-runtime') || !report.ledRequests.includes('led-strip-field'))
     failures.push(`LED chunks not loaded: ${report.ledRequests.join(', ')}`);
 } else if (report.ledRequests.length) failures.push(`no strips but LED chunks requested: ${report.ledRequests.join(', ')}`);
 if (report.ledRequests.includes('led-strip-editor')) failures.push('the View loaded the LED editor chunk');
 report.failures = failures;
+report.partial = partial || undefined;
 const text = `${JSON.stringify(report, null, 2)}\n`;
 if (output) { mkdirSync(dirname(output), { recursive: true }); writeFileSync(output, text); }
-console.log(text);
+console.log(JSON.stringify({ ...report, rows: undefined }, null, 2));
 if (failures.length) { console.error(`led-strips-v1 ${size}: ${failures.length} failure(s)`); process.exit(1); }
diff --git a/demo/performance/README.md b/demo/performance/README.md
index 0e8d0ec8..5cde5e30 100644
--- a/demo/performance/README.md
+++ b/demo/performance/README.md
@@ -437,11 +437,21 @@ reduced motion; every sample is cold (a new browser and card), seven samples
 after one warm-up. The runner fails on its own against
 `budgets-led-strips.json` — the ТЗ table, median and p95: `firstStableRenderMs`
 3400/5000, `warmSpaceReadyMs` 1500, `stateUpdateMs` 1000/1500, `panZoomMs` 500,
-the longest pan/zoom Long Task 150 ms, retained heap after 20 A→B→C→A cycles
-64 MiB — and on exact counters: zero field geometry recomputes over 100
-unrelated HA ticks, 100 camera steps and a colour-only change, at most 50 cache
-entries, no cache growth over the cycles, the LED chunks loaded with strips
-and none without them, never the editor chunk in the View. Base predates the
+the longest pan/zoom Long Task 150 ms — of the interaction profile's camera
+scenario and of a 100-step series, one wheel step per frame — retained heap
+after 20 A→B→C→A cycles 64 MiB — and on exact counters: zero field geometry
+recomputes over 100 unrelated HA ticks, 100 camera steps and a colour-only
+change; the three caches of the shown space (`ledStats` of the runtime chunk)
+— shapes ≤ 50, visibility ≤ 50, retained per-emitter fans ≤ 2500 — identical
+after every cycle; after disconnect 0 retained entries and 0 live LED
+timers/frames/observers (tracked by creation stack in the page); one extra
+cold run holds the runtime response, removes the card meanwhile and requires
+that the landed chunk renders, caches and schedules nothing for it; the LED
+chunks loaded with strips and none without them, never the editor chunk in
+the View. A runner with a short step limit may collect the samples in parts
+(`--warmup-only`, `--samples=N --no-late-import`) and judge them with
+`--merge=…` — the same cold samples, the same gates, the minimum of seven
+samples after one warm-up enforced on the merged set. Base predates the
 strips, so there is no relative comparison; the zero-LED View remains judged
 by the relative `large-house-interaction-v1` profile. Exact-SHA Linux output
 of the full performance workflow (`led-strips` matrix entry) is the gate
diff --git a/demo/performance/budgets-led-strips.json b/demo/performance/budgets-led-strips.json
index 01c86c48..e3a5ba08 100644
--- a/demo/performance/budgets-led-strips.json
+++ b/demo/performance/budgets-led-strips.json
@@ -1,8 +1,12 @@
 {
   "profile": "led-strips-v1",
   "issue": 780,
-  "note": "ТЗ #780 §13.2: absolute limits applied to median and p95; 10x5 rests on the interaction profile's absolute ceilings, 50x50 are the acceptance bounds set in the ТЗ. The no-strip control is judged by the existing interaction profile against base.",
-  "cacheEntries": 50,
+  "note": "ТЗ #780 §13.2: absolute limits applied to median and p95; 10x5 rests on the interaction profile's absolute ceilings, 50x50 are the acceptance bounds set in the ТЗ. The no-strip control is judged by the existing interaction profile against base. Caches of the shown space (ТЗ §13.2): 50 shapes, 50 visibility entries, 2500 retained per-emitter fans; 0 after disconnect.",
+  "caches": {
+    "shapes": 50,
+    "visibility": 50,
+    "sources": 2500
+  },
   "sizes": {
     "10x5": {
       "firstStableRenderMs": 3400,
@@ -10,7 +14,8 @@
       "stateUpdateMs": 1000,
       "panZoomMs": 500,
       "panZoomLongTaskMaxMs": 150,
-      "retainedHeapBytes": 67108864
+      "retainedHeapBytes": 67108864,
+      "cameraSeriesLongTaskMaxMs": 150
     },
     "50x50": {
       "firstStableRenderMs": 5000,
@@ -18,7 +23,8 @@
       "stateUpdateMs": 1500,
       "panZoomMs": 500,
       "panZoomLongTaskMaxMs": 150,
-      "retainedHeapBytes": 67108864
+      "retainedHeapBytes": 67108864,
+      "cameraSeriesLongTaskMaxMs": 150
     },
     "none": {}
   }
diff --git a/docs/LIGHT.md b/docs/LIGHT.md
index b737f769..8b5e8fae 100644
--- a/docs/LIGHT.md
+++ b/docs/LIGHT.md
@@ -451,4 +451,5 @@ only the geometry differs:
 - **Laziness.** The stripe/hit/2.5D code (`led-strip-runtime`) and the field
   (`led-strip-field`) are separate lazy chunks; the initial graph holds only
   the presence check and the loader (`led-strip-gate`). Caches are bounded per
-  space (50 shapes, 50 visibilities) and released on space change.
+  space (50 shapes, 50 visibilities, 2500 retained fans) and released on space
+  change and on disconnect; a chunk that lands after disconnect applies nothing.
diff --git a/src/houseplan-card.ts b/src/houseplan-card.ts
index 159185ae..ae2261ab 100755
--- a/src/houseplan-card.ts
+++ b/src/houseplan-card.ts
@@ -6,7 +6,7 @@
  *  2) LEGACY fallback — baked-in country-house data (src/data/*), coordinates in a 1489×1053 canvas.
  * The icon layout is stored on the server (houseplan/layout/*), fallback — localStorage.
  */
-import { ledAnchor, ledRuntime, ledStripsByMarker, ledVisible } from './led-strip-gate';
+import { ledAnchor, ledRelease, ledRuntime, ledStripsByMarker, ledVisible } from './led-strip-gate';
 import { ledButton, ledEditorFor, ledHistory, ledImportNote, ledSection, ledWallsNote } from './led-strip-card';
 import { LitElement, html, svg, nothing, noChange, TemplateResult, PropertyValues, type PropertyDeclaration } from 'lit';
 import { cache as litCache } from 'lit/directives/cache.js';
@@ -2772,6 +2772,7 @@ export class HouseplanCard extends LitElement {
     this._continuityHistory = [...this._continuityHistory, ...this._continuity.trace].slice(-80);
     this._continuity.dispose();
     this._continuityDisposed = true;
+    ledRelease(this); // #780 r1 M5: no retained LED cache after disconnect
     super.disconnectedCallback();
   }
 
@@ -10509,8 +10510,9 @@ export class HouseplanCard extends LitElement {
 
   /** #780: the lazy LED chunk when the space shows a strip (ТЗ §13.1). */
   private _ledRt(space: SpaceModel) {
-    return ledVisible(space, this._renderDevices, this._mode === 'devices' && this._showAll, this._serverCfg?.markers)
-      ? ledRuntime(space.id, () => this.requestUpdate()) : null;
+    // A disconnected card never applies the chunk (a late import, r1 M5).
+    return this.isConnected && ledVisible(space, this._renderDevices, this._mode === 'devices' && this._showAll, this._serverCfg?.markers)
+      ? ledRuntime(space.id, () => this.isConnected && this.requestUpdate()) : null;
   }
 
   /** #780: the Devices-editor LED tool, its own lazy chunk (src/led-strip-card.ts). */
diff --git a/src/led-strip-field.ts b/src/led-strip-field.ts
index d116afcc..f796744c 100644
--- a/src/led-strip-field.ts
+++ b/src/led-strip-field.ts
@@ -96,6 +96,12 @@ export class LedFieldCache {
     return value;
   }
   clear(): void { this.entries.clear(); this.ids.clear(); this.space = ''; }
+  /** Retained visibility fans (the per-emitter source cache, ТЗ §13.2: ≤ 2500). */
+  get sources(): number {
+    let n = 0;
+    for (const value of this.entries.values()) for (const piece of value?.pieces || []) n += piece.clip?.length ?? 0;
+    return n;
+  }
 }
 
 const pointsKey = (points: readonly number[][]): string =>
@@ -234,6 +240,16 @@ export interface LedFieldInput {
 }
 
 const fieldCaches = new WeakMap<object, LedFieldCache>();
+/** Disconnect (ТЗ §13.2): no retained entry of this owner. */
+export function releaseLedField(owner: object): void {
+  fieldCaches.get(owner)?.clear();
+  fieldCaches.delete(owner);
+}
+/** The performance witness: what this owner retains right now. */
+export function ledFieldStats(owner: object): { visibility: number; sources: number; recomputes: number } {
+  const cache = fieldCaches.get(owner);
+  return { visibility: cache?.size ?? 0, sources: cache?.sources ?? 0, recomputes: cache?.recomputes ?? 0 };
+}
 export function ledFieldCache(owner: object): LedFieldCache {
   let cache = fieldCaches.get(owner);
   if (!cache) {
diff --git a/src/led-strip-gate.ts b/src/led-strip-gate.ts
index 847548eb..b2c51d17 100644
--- a/src/led-strip-gate.ts
+++ b/src/led-strip-gate.ts
@@ -89,6 +89,9 @@ export function ledRuntime(entry: string, ready: () => void): LedRuntime | null
     '__HOUSEPLAN_LED_RETRY_ASSET__', (module) => module.LED_RUNTIME_FINGERPRINT);
 }
 
+/** Disconnect: release this card's LED caches if the chunk is here (ТЗ §13.2). */
+export function ledRelease(owner: object): void { runtimeSlot.module?.releaseLed(owner); }
+
 /** The Devices-editor LED tool chunk (ТЗ §13.1): only on an explicit entry. */
 export function ledEditorModule(entry: string, ready: () => void): LedEditorModule | null {
   return lazy(editorSlot, entry, ready, () => import('./led-strip-editor'),
diff --git a/src/led-strip-runtime.ts b/src/led-strip-runtime.ts
index 37669d3f..c7520774 100755
--- a/src/led-strip-runtime.ts
+++ b/src/led-strip-runtime.ts
@@ -413,6 +413,8 @@ export function ledFrame(input: LedFrameInput): LedFrame {
 // (ТЗ §13.1). The host is the card itself, read structurally.
 
 export interface LedCardHost {
+  /** A late chunk never re-renders (and re-fills caches of) a disconnected card. */
+  isConnected?: boolean;
   _renderDevices: readonly DevItem[];
   _renderPlanHass: any; // any-ok: the card's HA snapshot type is internal to the card
   _virtualLights: VirtualLightSnapshot;
@@ -443,6 +445,18 @@ export interface LedCardHost {
 
 const frames = new WeakMap<object, { key: unknown[]; frame: LedFrame }>();
 
+/** Disconnect (ТЗ §13.2, r1 M5): the frame and the field caches of this card are released. */
+export function releaseLed(owner: object): void {
+  frames.delete(owner);
+  field?.releaseLedField(owner);
+}
+
+/** The performance witness: shapes (frame), visibility entries and retained fans of this card. */
+export function ledStats(owner: object): { shapes: number; visibility: number; sources: number; recomputes: number } {
+  return { shapes: frames.get(owner)?.frame.views.length ?? 0,
+    ...(field?.ledFieldStats(owner) ?? { visibility: 0, sources: 0, recomputes: 0 }) };
+}
+
 /** The LED frame of a space for this card, rebuilt only when an input changed. */
 export function ledFrameFor(host: LedCardHost, space: SpaceModel, spaceGlow: boolean): LedFrame {
   const polygons = space.rooms.flatMap((room) => {
@@ -472,7 +486,8 @@ export function ledFrameFor(host: LedCardHost, space: SpaceModel, spaceGlow: boo
     inRoom: (point, room) => host._pointInRoom(point, room),
     showHidden: host._mode === 'devices' && host._showAll,
   });
-  frames.set(host, { key, frame });
+  // A disconnected card keeps nothing (a pending update after disconnect, r1 M5).
+  if (host.isConnected !== false) frames.set(host, { key, frame });
   return frame;
 }
 
@@ -524,8 +539,9 @@ export function renderLedLayerFor(
 }
 
 export function renderLedFieldFor(host: LedCardHost, space: SpaceModel, spaceGlow: boolean): TemplateResult {
+  if (host.isConnected === false) return svg`` as unknown as TemplateResult;
   const frame = ledFrameFor(host, space, spaceGlow);
-  const module = frame.scene && fieldWanted(frame.views) ? ledField(space.id, () => host.requestUpdate()) : null;
+  const module = frame.scene && fieldWanted(frame.views) ? ledField(space.id, () => host.isConnected !== false && host.requestUpdate()) : null;
   if (!module) return svg`` as unknown as TemplateResult;
   return module.renderLedField({
     views: frame.views,
diff --git a/test/led-strip-runtime.test.mjs b/test/led-strip-runtime.test.mjs
index 39b3e0f0..e10e8e8d 100644
--- a/test/led-strip-runtime.test.mjs
+++ b/test/led-strip-runtime.test.mjs
@@ -158,3 +158,16 @@ test('AC2/r1 M2: an explicit valid room_id wins over the anchor room; a stale on
   assert.equal(stripRoom(rooms, null, [250, 100], inA)?.id, 'A');
   assert.equal(stripRoom(rooms, null, null, inA), undefined);
 });
+
+test('AC17/r1 M5: a released owner retains nothing; the stats count visibility entries and fans', async () => {
+  const { ledFieldCache, ledFieldStats, releaseLedField } = await import('../test-build/led-strip-field.js');
+  const owner = {};
+  const cache = ledFieldCache(owner);
+  cache.forSpace('a');
+  cache.read('k1', () => ({ pieces: [{ d: 'M0 0', clip: ['M0 0 Z', 'M1 1 Z'] }, { d: 'M1 1', clip: null }], box: { x: 0, y: 0, w: 1, h: 1 } }));
+  cache.read('k2', () => null);
+  assert.deepEqual(ledFieldStats(owner), { visibility: 2, sources: 2, recomputes: 2 });
+  releaseLedField(owner);
+  assert.deepEqual(ledFieldStats(owner), { visibility: 0, sources: 0, recomputes: 0 });
+  assert.notEqual(ledFieldCache(owner), cache, 'a new mount starts a new cache');
+});
diff --git a/test/performance-workflow.test.mjs b/test/performance-workflow.test.mjs
index 5863be9d..d7a5c7c5 100644
--- a/test/performance-workflow.test.mjs
+++ b/test/performance-workflow.test.mjs
@@ -305,8 +305,9 @@ test('#780 led-strips-v1: the derived fixture converts devices without adding ic
   }
   const budgets = JSON.parse(readFileSync(new URL('../demo/performance/budgets-led-strips.json', import.meta.url), 'utf8'));
   assert.deepEqual(budgets.sizes['10x5'], { firstStableRenderMs: 3400, warmSpaceReadyMs: 1500, stateUpdateMs: 1000,
-    panZoomMs: 500, panZoomLongTaskMaxMs: 150, retainedHeapBytes: 64 * 1024 * 1024 });
+    panZoomMs: 500, panZoomLongTaskMaxMs: 150, retainedHeapBytes: 64 * 1024 * 1024, cameraSeriesLongTaskMaxMs: 150 });
   assert.deepEqual(budgets.sizes['50x50'], { firstStableRenderMs: 5000, warmSpaceReadyMs: 1500, stateUpdateMs: 1500,
-    panZoomMs: 500, panZoomLongTaskMaxMs: 150, retainedHeapBytes: 64 * 1024 * 1024 });
-  assert.equal(budgets.cacheEntries, 50);
+    panZoomMs: 500, panZoomLongTaskMaxMs: 150, retainedHeapBytes: 64 * 1024 * 1024, cameraSeriesLongTaskMaxMs: 150 });
+  // ТЗ §13.2: the three caches of the shown space, judged separately (r1 M5).
+  assert.deepEqual(budgets.caches, { shapes: 50, visibility: 50, sources: 2500 });
 });