---
phase: 04-harden-clean-up-optional
plan: 04
subsystem: testing
tags:
  - uat-harness
  - a33
  - sw-state-persistence
  - sw-eviction
  - spike-first
  - spike-failed
  - cdp-worker-close
  - roadmap-sc-1-open
  - charter-d-p4-01
  - phase-4-wave-3
  - plan-fix-ceremony-needed

requires:
  - phase: 01-stabilize-video-pipeline
    provides: "src/offscreen/recorder.ts:91 `let segments: Blob[] = []` module-level RAM-only buffer — the canonical Plan 01-07 D-13 restart-segments architecture (3 × 10s self-contained WebM segments, RAM-only, no persistence layer). Plan 04-04 Wave 0 SPIKE empirically tested whether this RAM-only design survives a 5-min SW idle + Puppeteer CDP worker.close() — outcome below."
  - phase: 03-spec-10-smoke-verification-dom-event-log-verification
    provides: "Plan 03-01/03-02/03-03 cs-injection-world + harness-internal SAVE_ARCHIVE dispatch pattern (chrome.runtime.sendMessage from harness-page realm). Plan 04-04 spike reuses this dispatch pattern verbatim per REVISION iter-2 Option B (no new __mokoshHarness method)."
  - plan: 04-01
    provides: "audit P1 polish baseline (vitest 180 → preserved at 183 by Plan 04-02 + Plan 04-03)."
  - plan: 04-02
    provides: "Tier-1 FORBIDDEN_HOOK_STRINGS inventory at 12 entries; SW chunk `new Function`=0 + `eval`=0 baseline. Plan 04-04 made zero source-code changes so all bundle gates remain unchanged from Plan 04-02 polarity."
  - plan: 04-03
    provides: "A29 strict-sentinel flake closure; UAT harness 33/33 GREEN baseline; vitest 183/183 GREEN baseline (subject to documented pre-existing flakes when run in parallel — see Issues Encountered below). Plan 04-04 preserves both baselines because Task 2 (which would have flipped UAT 33→34) is BLOCKED by the spike outcome."

provides:
  - "Empirical evidence (one full HEADLESS=1 spike run; reproducible script committed) that the current offscreen-document `segments: Blob[] = []` RAM-only architecture does NOT survive 5 minutes of SW idle followed by Puppeteer CDP `worker.close()`. videoSize after SAVE = 8505 bytes vs the 100 KB sanity floor (typical healthy 30s archive = 1-3 MB). The 8505 bytes are corrupt WebM (ffprobe: 'End of file' + 'Duplicate element' errors with no valid clusters); rrweb/session.json = []; logs/events.json = []; meta.urls = chrome-extension://* only (real-page URLs lost). REFUTES the RESEARCH Q2 MEDIUM-confidence hypothesis (A3) that the offscreen has an independent lifecycle anchored by active MediaRecorder."
  - "stopServiceWorker(browser, extensionId) helper at tests/uat/lib/harness-page-driver.ts (verbatim Chrome devrel canonical pattern; Puppeteer >=22.1.0; project pin ^25 OK). Future plan-fix work (IndexedDB persistence) reuses this helper to verify whatever persistence layer it adds actually closes ROADMAP SC #1. Persisting artifact even though Task 2 is BLOCKED — the helper is non-empty contract scaffolding for the eventual plan-fix's verification harness."
  - "tests/uat/spike-a33-sw-persistence.ts one-shot reproducible empirical investigation script. Committed (not deleted) so the eventual IndexedDB-persistence plan-fix can re-run the spike to verify its fix closes the gap. Reusable for any future SW-lifecycle regression testing."
  - "findLatestZip exported from tests/uat/lib/harness-page-driver.ts (was private; visibility expanded for the spike script's archive enumeration). Read-only convenience; no semantic change."
  - "Definitive ROADMAP SC #1 status: OPEN. The 5-min idle empirical test produces an essentially-empty zip; the spec contract ('produces a non-empty video buffer') is NOT met by the current architecture. Closes the spike question with an unambiguous NO."

affects:
  - "ROADMAP SC #1 (SW state persistence across 30s idle) — REMAINS OPEN. Plan 04-04 was the spike-first investigation of whether SC #1 closes for free under the current architecture (RESEARCH MEDIUM-confidence hypothesis: yes); spike returned NO. The next plan(s) MUST add a persistence layer (canonical recommendation: IndexedDB-in-offscreen per RESEARCH Q2 sub-question b Option C; Blobs serialize cleanly via structured-clone; per-segment write ~3 MB; ~3 writes per 30s window). That work is OUT OF SCOPE for Plan 04-04 (the spike-first contract is explicit: 'if FAILED, STOP — propose plan-fix ceremony; do NOT improvise inline')."
  - "Saved memory `feedback-gsd-ceremony-for-fixes.md` invoked — architectural change of this magnitude (moving the segment buffer from offscreen RAM to IndexedDB; new I/O paths; per-segment write; new failure modes) is a Rule 4 (Architectural Change). MUST route through /gsd-plan-phase rewrite OR /gsd-debug ceremony, NOT inline plan execution. Plan 04-04 stops at Task 1 with this SUMMARY documenting the failure mode + the recommended remediation."
  - "Saved memory `feedback-no-unilateral-scope-reduction.md` honored — full spike was run to completion (~5 min wall-clock idle + ~8s orchestration; total 308.7s); no scope reduction; the failed outcome is the canonical decision-point that the spike-first contract was DESIGNED to surface BEFORE expanding scope into wider persistence work. The decision to STOP is the contract executing as designed, NOT a scope reduction."
  - "Future Phase 4 plan numbering — Plan 04-05/04-06/04-07 remain queued for their respective concerns (per 04-CONTEXT.md §'Claude's Discretion' planner suggestion: 04-05 build hygiene wave already closed; 04-06 visual polish; 04-07 closure). The IndexedDB persistence plan-fix (to close ROADMAP SC #1) is a NEW plan, likely 04-08 or inserted ahead via /gsd-plan-phase re-run. The plan-checker/planner owns the numbering decision."
  - "UAT harness count stays at 33 (A33 was NOT added because Task 2 was BLOCKED by the spike outcome). When the persistence plan-fix eventually lands, A33 (or A33-equivalent name) becomes a verification gate on the new persistence layer — repurposing the spike methodology as a repeatable regression test."

tech-stack:
  added: []
  patterns:
    - "Spike-first investigation protocol (NEW for Plan 04-04 / Phase 4): when a plan's architectural assumption is MEDIUM-confidence per RESEARCH, the planner shapes the plan as `type: spike→auto` with Wave 0 = empirical investigation + decision gate + Wave 1 = implementation conditional on spike outcome. If spike PASSES, Wave 1 proceeds with verification-only work; if spike FAILS, Wave 1 is BLOCKED + the failure mode is documented + a plan-fix ceremony route is proposed. This pattern is the canonical risk hedge for HIGH/MEDIUM-confidence architectural assumptions (see Plan 01-07 D-13 restart-segments pivot as the originating precedent; Plan 04-04 is the second deployment)."
    - "Puppeteer CDP `worker.close()` SW-eviction simulation (verbatim from Chrome devrel — https://developer.chrome.com/docs/extensions/how-to/test/test-serviceworker-termination-with-puppeteer). Required because Puppeteer's persistent CDP attach keeps SWs alive indefinitely; natural 30s idle eviction does NOT fire under test conditions. The helper `stopServiceWorker(browser, extensionId)` is now available at tests/uat/lib/harness-page-driver.ts for any future SW-lifecycle test (including the eventual persistence-layer-verification A33)."
    - "Forensic-evidence committed spike script (NEW): when a spike FAILS, the script is committed (not deleted) so the eventual plan-fix can re-run the exact reproducible test that revealed the failure — sealing the verification contract end-to-end. Compare with successful spikes which the planner may delete if a verification-only harness assertion superseded it."

key-files:
  modified:
    - "tests/uat/lib/harness-page-driver.ts — Added `stopServiceWorker(browser, extensionId)` helper near top of file (after existing imports + interface) with full Chrome-devrel docstring citing 3 canonical references. Added `Browser` to puppeteer type import. Exported `findLatestZip` (was private — visibility expanded for the spike script reuse without code duplication). Other driveA* functions UNCHANGED. Net change: +43 / -6 lines."
  created:
    - "tests/uat/spike-a33-sw-persistence.ts — One-shot empirical investigation script (202 lines incl. extensive docstring). Reuses launchHarnessBrowser + stopServiceWorker + findLatestZip; primes recording via __mokoshHarness.assertA2 (canonical 'go to REC state' method per REVISION iter-2 Option B); 5-min wall-clock idle; stopServiceWorker; 500ms settle; chrome.runtime.sendMessage({type: 'SAVE_ARCHIVE'}, ...) inline from harness-page realm; 5s download settle; findLatestZip + JSZip.loadAsync + video/last_30sec.webm extraction; PASS/FAIL gate at 100_000 bytes. Exit code 0 = PASSED, 1 = FAILED. Committed (not deleted) per the forensic-evidence pattern — the eventual persistence plan-fix re-runs this script to verify the fix."
    - ".planning/phases/04-harden-clean-up-optional/04-04-SUMMARY.md — this file."

key-decisions:
  - "Honor the spike-first contract — STOP at Task 1 because the gating condition on Task 2 (videoSize > 100_000) is NOT met (got 8505). Per the plan's <spike_contract>: 'If offscreen does NOT survive: STOP execution. Return to orchestrator with finding + propose alternative (e.g., IndexedDB persistence) via proper plan-fix ceremony per feedback-gsd-ceremony-for-fixes.md. Do NOT improvise a fix inside this plan.' Decision made: STOP, write this SUMMARY, return to orchestrator. NO inline fix. NO Task 2 work. The plan-checker / planner owns the next move."
  - "Commit the spike script (not delete) — per the plan text 'OK to delete OR keep committed as tests/uat/spike-*.ts for future SW-lifecycle investigations'. Decision made: KEEP. Rationale: (a) the script is the canonical reproducible regression test for the eventual persistence plan-fix; (b) forensic evidence of WHAT was tested + HOW + the exact numbers; (c) future maintainers grep'ing for 'sw-persistence' or 'stopServiceWorker' find both the helper and an executable usage example; (d) 202 lines of well-documented one-shot is cheap to keep around. Compare with successful spikes which the planner may delete if a verification-only harness assertion supersedes them — for FAILED spikes, the script is the contract."
  - "stopServiceWorker helper kept committed at tests/uat/lib/harness-page-driver.ts even though Task 2 is BLOCKED — the helper is a non-empty positive artifact whether or not A33 ever lands. Future plan-fix verification harness (e.g., post-IndexedDB-persistence A33) reuses it directly. Cost of keeping: +43 LOC of well-documented helper code at a sensible location. Cost of removing: lose the exact Chrome-devrel-cited canonical reference pattern; have to re-derive it next time. Keep wins."
  - "ROADMAP SC #1 status NOT flipped to GREEN — remains OPEN. The spike-first contract's whole point is that an empirical NO answer reopens the requirement, not closes it. Updating the ROADMAP table to 'CLOSED — spike PASSED' would be a lie; updating to 'CLOSED — spike FAILED' would be a category error (you don't close a SC by proving it's broken). Correct action: leave SC #1 OPEN; document the spike result in this SUMMARY + the eventual plan-fix's plan/summary references it as 'closes SC #1'."
  - "No SUMMARY-level operator empirical UAT requested per saved memory `feedback-trust-harness-over-manual-uat.md` — the empirical evidence IS the spike script's run output; there's no operator-time-saved opportunity for a manual UAT replay. The operator's role here is the next-step ceremony decision (route to /gsd-debug or /gsd-plan-phase rewrite), not a click-through verification."
  - "Pre-checkpoint bundle gates run + GREEN per saved memory `feedback-pre-checkpoint-bundle-gates.md`. Plan 04-04 modifies ONLY tests/uat/* + adds a one-shot script — zero production source changes — so the bundle gates trivially hold from the Plan 04-02 baseline. Verified live (numbers in 'Verification — Pre-Checkpoint Bundle Gates' section below)."
  - "Pre-existing parallel-vitest flake (3 tests) observed during sequential `npm test` run; all 3 PASS in isolation. Per 04-CONTEXT.md items 9 + 10 these are documented pre-existing issues (Phase 4 future plan owns flake stabilization). NOT a Plan 04-04 regression — Plan 04-04 made zero source-code changes that could possibly affect tests/background/blob-url-download.test.ts, tests/background/webm-remux.test.ts, or tests/offscreen/webm-playback.test.ts."

patterns-established:
  - "Spike-FAILED forensic-evidence pattern: when a spike fails, commit the spike script (not delete), commit any positive artifacts (helpers, type imports, visibility expansions) atomically with the spike script, write a SUMMARY documenting the exact failure numbers + reproducibility instructions + recommended remediation path, STOP plan execution at the gating-condition boundary, return to orchestrator. The next plan in the sequence becomes a plan-fix that re-uses the spike script as its own regression-verification gate."
  - "Atomic commit format for spike-failed Wave 0: `feat({phase}-{plan}): Wave 0 spike — {helper-name} helper + {N}-{unit} {investigation-target} empirical result`. The commit subject states what the spike investigated; the commit body documents the OUTCOME with explicit numerical evidence + an interpretation paragraph + the next-step routing. Used here: `feat(04-04): Wave 0 spike — stopServiceWorker helper + 5-min SW idle empirical result`."

requirements-completed: []

# Metrics
duration: "~25 min"
completed: 2026-05-21
---

# Phase 04 Plan 04: SW state persistence spike — empirical NO, plan-fix ceremony required

**Wave 0 SPIKE empirically refutes RESEARCH Q2 MEDIUM-confidence hypothesis A3 (offscreen-document independent lifecycle anchored by active MediaRecorder): the current `src/offscreen/recorder.ts:91 let segments: Blob[] = []` RAM-only architecture does NOT survive 5 minutes of SW idle + Puppeteer CDP `worker.close()`. Measured `video/last_30sec.webm` post-SAVE = 8505 bytes (broken WebM per ffprobe; no valid clusters; rrweb + events.json + meta.urls all empty/lost). Spike-first contract triggers — Task 2 (A33 verification-only harness assertion) BLOCKED; ROADMAP SC #1 remains OPEN; architectural change (IndexedDB persistence per RESEARCH Q2 sub-question b Option C) routes through plan-fix ceremony per saved-memory contract. Persisting positive artifacts committed: `stopServiceWorker(browser, extensionId)` helper (verbatim Chrome-devrel canonical pattern) at tests/uat/lib/harness-page-driver.ts + tests/uat/spike-a33-sw-persistence.ts forensic-evidence one-shot script. UAT harness stays at 33/33 GREEN (A33 NOT added); vitest baseline 183 preserved (3 pre-existing parallel-vitest flakes pass in isolation per 04-CONTEXT items 9-10).**

## Performance

- **Duration:** ~25 min (Phase 4 Wave 3; fourth plan in execution order)
- **Started:** 2026-05-21T16:32:00Z (executor re-spawn after prior agent confusion; took on-disk Wave 0 work as-is per the re-spawn handoff)
- **Completed:** 2026-05-21T18:55:00Z (this SUMMARY committed)
- **Tasks:** 1 of 2 plan tasks complete (Task 1: Wave 0 SPIKE; Task 2: BLOCKED by spike outcome per the gating condition)
- **Files modified:** 2 (tests/uat/lib/harness-page-driver.ts +43 / -6; tests/uat/spike-a33-sw-persistence.ts NEW +202)
- **Production source changes:** 0 (Plan 04-04 made ZERO source-code edits to src/*; only adds tests/uat/* artifacts)

## Accomplishments

- **Wave 0 SPIKE executed end-to-end** (Task 1): 308.7s wall-clock (~5min idle + ~8s orchestration). Step 1 assertA2 prime → REC state achieved; Step 2 5-min idle elapsed cleanly; Step 3 stopServiceWorker via Puppeteer CDP worker.close() succeeded; Step 4 500ms settle; Step 5 SAVE_ARCHIVE dispatch inline from harness-page realm via `chrome.runtime.sendMessage({type: 'SAVE_ARCHIVE'}, cb)` returned `{success: true}` (SW respawned event-driven on the message); Step 6 5s download settle; Step 7 findLatestZip + JSZip.loadAsync + `video/last_30sec.webm` extraction. Empirical numbers logged.
- **Empirical refutation of RESEARCH MEDIUM-confidence hypothesis A3**: `videoSize = 8505 bytes` (sanity floor was 100 KB; typical healthy archive 1-3 MB). The 8505 bytes are corrupt WebM per ffprobe (`End of file` + `Duplicate element` errors; no valid clusters). Companion zip entries also empty/lost: `rrweb/session.json=[]`, `logs/events.json=[]`, `meta.urls=[chrome-extension://*]` (real-page URLs LOST — confirms the SW tab tracker was reset across the SW death + the active probe tab navigated state vanished too). Conclusive empirical NO.
- **stopServiceWorker helper landed** (Task 1 persisting artifact): canonical Chrome-devrel pattern at tests/uat/lib/harness-page-driver.ts:68-80. `await browser.waitForTarget(t => t.type() === 'service_worker' && t.url().startsWith(\`chrome-extension://\${extensionId}\`))` → `target.worker()?.close()`. Docstring cites 3 authoritative references including the Chrome blog post on eyeOS's MV3 SW suspension testing journey.
- **Spike script committed** (Task 1 forensic evidence): tests/uat/spike-a33-sw-persistence.ts is 202 lines incl. extensive docstring documenting: spike outcome decision tree, architectural reuse rationale (assertA2 prime + chrome.runtime.sendMessage SAVE; both REVISION iter-2 Option B verified), references to PLAN.md + RESEARCH.md + Chrome docs. Future plan-fix re-runs this script as its regression-verification gate.
- **Task 2 gating condition documented as NOT MET**: per the plan's Task 2 `<action>` first sentence — `**GATING CONDITION:** Task 1 spike produced videoSize > 100_000. (If FAILED, this task is BLOCKED and the plan must be re-planned to add IndexedDB persistence work.)` — measured videoSize=8505 < 100_000, so Task 2 is BLOCKED. No code added for Task 2; UAT count stays at 33; FORBIDDEN_HOOK_STRINGS inventory unchanged at 12; A33 not introduced.
- **ROADMAP SC #1 status communicated as OPEN**: leaving the ROADMAP success-criteria row unflipped (cannot mark CLOSED on a FAILED spike). The next plan-fix's SUMMARY will close it when the persistence layer lands + the spike script is re-run + PASSES.

## Task Commits

Each plan task was committed atomically with normal git commits + pre-commit hooks (sequential foreground mode, in-line with Plans 04-01 + 04-02 + 04-03's protocol):

1. **Task 1: Wave 0 SPIKE — stopServiceWorker helper + 5-min SW idle empirical result** — `3726eee` (feat). Adds Browser type to puppeteer import; adds `stopServiceWorker(browser, extensionId)` helper (verbatim Chrome-devrel canonical) at top of tests/uat/lib/harness-page-driver.ts; exports `findLatestZip` (was module-internal). Creates tests/uat/spike-a33-sw-persistence.ts one-shot reproducible spike script. Spike RAN to completion with explicit `videoSize=8505 bytes (floor=100000; elapsed=308.7s)` line + `SPIKE OUTCOME: FAILED (offscreen DIED — videoSize below floor)`. Acceptance criteria all met for the FAIL branch (script completed, no Puppeteer throw, explicit videoSize line, SAVE_ARCHIVE dispatch verified to use `chrome.runtime.sendMessage` not `dispatchSaveArchive`).

2. **Task 2: A33 SW state persistence harness assertion** — **BLOCKED, NOT COMMITTED**. Per the plan's explicit gating condition (`If FAILED, this task is BLOCKED and the plan must be re-planned to add IndexedDB persistence work.`), no code was added; no UAT count flip; no FORBIDDEN_HOOK_STRINGS lockstep update; no orchestrator wiring. The re-planning event is delegated to /gsd-plan-phase rewrite OR /gsd-debug ceremony per saved-memory `feedback-gsd-ceremony-for-fixes.md`.

**Plan metadata commit (will follow):** `docs(04-04): complete harden-clean-up-optional plan 04-04 — SW persistence spike FAILED, plan-fix ceremony required` — includes this SUMMARY.md + STATE.md + ROADMAP.md updates.

## Files Created/Modified

- `tests/uat/lib/harness-page-driver.ts` — **MODIFIED.** +43 / -6 lines. Added Browser type to puppeteer import at line 43. Added `stopServiceWorker(browser, extensionId)` helper as exported async function near top of file (after existing imports + assertion-record interface) — verbatim Chrome-devrel canonical pattern with full docstring + 3 authoritative reference URLs. Exported `findLatestZip` (was module-internal); docstring updated to cite Plan 04-04 reuse rationale. Other driveA* / driveA1..driveA32 functions UNCHANGED.
- `tests/uat/spike-a33-sw-persistence.ts` — **CREATED.** 202 lines. One-shot reproducible empirical investigation script. Imports `launchHarnessBrowser` (from `./lib/launch.ts`) + `stopServiceWorker` + `findLatestZip` (from `./lib/harness-page-driver.ts`) + JSZip + readFileSync. Step 1 prime via `__mokoshHarness.assertA2`; Step 2 5-min wall-clock idle; Step 3 stopServiceWorker; Step 4 settle; Step 5 inline `chrome.runtime.sendMessage({type: 'SAVE_ARCHIVE'}, cb)` from harness-page realm; Step 6 download settle; Step 7 findLatestZip + JSZip + extract `video/last_30sec.webm`. PASS/FAIL gate at 100_000 bytes; exit code 0 = PASSED, 1 = FAILED. Run with `HEADLESS=1 tsx tests/uat/spike-a33-sw-persistence.ts`.
- `.planning/phases/04-harden-clean-up-optional/04-04-SUMMARY.md` — **CREATED** (this file).

## Decisions Made

See `key-decisions` in frontmatter for the canonical list. Highlights:

1. **Honor spike-first contract** — STOP at Task 1; do NOT improvise inline.
2. **Commit (not delete) spike script** — forensic evidence + future regression test.
3. **Keep stopServiceWorker helper** — non-empty positive artifact independent of Task 2 status.
4. **ROADMAP SC #1 stays OPEN** — cannot mark CLOSED on a FAILED spike.
5. **Saved memory `feedback-gsd-ceremony-for-fixes.md` applied** — architectural fix routes through plan-fix ceremony.
6. **Saved memory `feedback-no-unilateral-scope-reduction.md` honored** — full 5-min spike was run to completion; the STOP decision is the spike-first contract executing as designed, not a unilateral scope reduction.
7. **Pre-existing parallel-vitest flakes are NOT in Plan 04-04 scope** — documented in CONTEXT items 9-10; pass in isolation; Plan 04-04 made zero source-code changes that could possibly affect them.

## Deviations from Plan

**None at the code level — plan executed exactly as written through the spike-first decision point.** The decision tree at line 64-70 of the plan (`<objective>` section: "Wave 0 (spike): A30-min empirical investigation. ... Wave 1 (impl): Based on spike outcome ... if spike FAILS ... A33 implementation expands per RESEARCH Q2 sub-question (b) recommendation (Option C: IndexedDB persistence in offscreen) ... This is a wider plan rewrite; the plan-checker should flag for re-planning if it materializes.") + the explicit Task 2 GATING CONDITION at line 345 (`**GATING CONDITION:** Task 1 spike produced videoSize > 100_000. (If FAILED, this task is BLOCKED and the plan must be re-planned to add IndexedDB persistence work.)`) both unambiguously specify the STOP-at-Task-1 outcome for spike failure. This SUMMARY documents that outcome verbatim.

**One process micro-deviation:** Plan was re-spawned with a fresh executor mid-flight (prior executor stalled after launching the spike; user authorized "preserve work, fresh executor continues" via GSD ceremony). Re-spawn adopted the on-disk Wave 0 work as-is (verified per-plan-spec via diff inspection before adopting). No code-level deviation; just orchestrator continuity.

**Total deviations:** 0 auto-fixes; 1 process-level executor re-spawn (handled per user's GSD ceremony invocation). Plan logic + contract honored verbatim.

## Issues Encountered

1. **Spike result was a FAILURE — but this is the spike contract working as designed.** The whole point of Wave 0 was to empirically test the RESEARCH MEDIUM-confidence assumption BEFORE expanding scope into Wave 1 work that would have been wasted if the assumption broke. The "issue" is properly framed not as an issue but as the spike's job: surface the empirical NO and route to plan-fix ceremony.

2. **Prior executor stalled / vanished without committing** — the re-spawn handoff document caught this; this fresh executor verified on-disk work matched plan spec, adopted it, ran the spike + committed Task 1 + wrote this SUMMARY. Total prior agent loss: ~64 minutes of wall-clock + no commits + no work-on-disk loss (Wave 0 work was already structured per-plan-spec and was the right thing to keep).

3. **vitest `npm test` (full sequential suite) showed 180/183 (3 failures) during pre-SUMMARY verification.** All 3 failures (`tests/background/blob-url-download.test.ts`, `tests/background/webm-remux.test.ts`, `tests/offscreen/webm-playback.test.ts`) PASS in isolation. Per 04-CONTEXT.md §"In scope" items 9-10 these are documented pre-existing flakes: "Pre-existing parallel-vitest Tier-1-build-step race (~1/5 full-suite runs)" + "2 pre-existing ffprobe/ffmpeg vitest flakes (pre-date Phase 3)". Plan 04-04 made ZERO source-code changes that could possibly affect those three test files — they are entirely about pre-Phase-4 production code. The flakes are out of Plan 04-04 scope; a future Phase 4 plan owns flake stabilization.

## Verification — Pre-Checkpoint Bundle Gates

Per saved memory `feedback-pre-checkpoint-bundle-gates.md` — these run on the production build output BEFORE any operator/empirical checkpoint or plan closure.

```
=== dist/assets/index-CgqXENQe.js (SW chunk) ===
new Function:  0    (Plan 04-02 polarity preserved — was 1 pre-04-02; now 0 since 04-02)
eval:          0    (Plan 04-02 baseline preserved)
Buffer.:       1    (JSZip bundled `buffer` polyfill — pre-existing per Plan 04-02 SUMMARY + deferred-items.md)
window.:       0    (DOM-globals in SW chunk gate — preserved)
document.:     0    (DOM-globals in SW chunk gate — preserved)

=== Tier-1 FORBIDDEN_HOOK_STRINGS inventory ===
tests/uat/harness.test.ts:                            12 entries  (10 core + 2 Plan 01-14 A23)
tests/background/no-test-hooks-in-prod-bundle.test.ts: 12 entries  (lockstep with the above)

=== dist/ grep against Tier-1 list (all 12 strings) ===
__mokoshTest                                       files-with-match: 0
setCurrentStream                                   files-with-match: 0
setSegmentCountGetter                              files-with-match: 0
installFakeDisplayMedia                            files-with-match: 0
uninstallFakeDisplayMedia                          files-with-match: 0
dispatchEndedOnTrack                               files-with-match: 0
getSegmentCount                                    files-with-match: 0
__mokoshOffscreenQuery                             files-with-match: 0
get-display-surface                                files-with-match: 0
get-segment-count                                  files-with-match: 0
lastGetDisplayMediaConstraints                     files-with-match: 0
get-last-getDisplayMedia-constraints               files-with-match: 0
```

**All 6/6 gates GREEN unchanged from Plan 04-03 baseline.** Plan 04-04 made zero production-source changes (only tests/uat/* + a one-shot script) so the gates trivially hold.

## SKIP_LONG_UAT Env-Gate Decision

The plan called for an `SKIP_LONG_UAT` env-gate to be wired into `tests/uat/harness.test.ts` as part of Task 2 to allow per-commit dev iteration to skip the 5-min A33 test. **This wiring was NOT added because Task 2 is BLOCKED** — no A33 means no need for the env-gate, no need for the orchestrator import/wrap/push lockstep. The env-gate becomes a Task-1 artifact of the eventual plan-fix that adds A33 against an IndexedDB-persistent buffer.

## Recommended Next Step (out of Plan 04-04 scope; routed to plan-fix ceremony)

Per the plan's `<objective>` section + saved memory `feedback-gsd-ceremony-for-fixes.md`:

**Route:** `/gsd-plan-phase` rewrite OR `/gsd-debug` ceremony — operator's choice. The new plan should:

1. **Architecture:** Implement RESEARCH Q2 sub-question (b) recommendation Option C — move `segments: Blob[]` from offscreen module-scope RAM into an IndexedDB store inside the offscreen document. Blobs serialize cleanly via structured-clone (no base64 encoding tax; native IDB shape). Per-segment write ~3 MB; ~3 writes per 30s window. RESEARCH notes IDB has no extension-context lifetime gotchas at this scale; Chrome enforces a default 30s minimum SW idle but the offscreen's own lifecycle (independent of SW per our spike) is the relevant constraint — which the spike just empirically refuted, so IDB persistence is the canonical fix.
2. **Verification harness:** A33 against the new persistence layer. The spike script at `tests/uat/spike-a33-sw-persistence.ts` is the canonical regression-verification gate — re-run it after the fix and it MUST exit 0 with `videoSize > 100_000`. Promote the spike methodology to a permanent harness assertion (assertA33 / driveA33 / orchestrator wiring + SKIP_LONG_UAT env-gate per the original Plan 04-04 Wave 1 spec).
3. **Files likely touched:** src/offscreen/recorder.ts (new IDB write path in the segment-rotation lifecycle); possibly a new src/offscreen/idb-segments.ts module; tests/offscreen/* unit tests; tests/uat/* harness assertion for A33; manifest.json may need adjusting (Chrome storage quota — though IDB doesn't require explicit permission).
4. **Risk:** the new I/O path adds failure modes (IDB quota exceeded; transaction abort; cross-context tab close during write). Plan-fix's THREAT MODEL needs to cover them.
5. **Cost:** likely 3-5 plan tasks across 2 waves. Phase 4 plan count grows from current 7 to ~8-9.
6. **Status communication:** ROADMAP SC #1 stays OPEN until the plan-fix's SUMMARY proves the spike script passes against the new architecture.

The plan-checker / planner owns whether to:
- (a) rewrite Plan 04-04 in-place (likely as Plan 04-04 v2 with `type: tdd` IDB-persistence work),
- (b) insert a new plan slot (e.g., Plan 04-08) for the persistence work + leave Plan 04-04's SUMMARY as the spike-findings record,
- (c) close Plan 04-04 as "spike concluded — outcome FAILED — see SUMMARY" + open a fresh Phase 4 follow-up plan slot for the IDB work.

Recommendation (this executor's read, non-binding): **Option (b) or (c)** — keep Plan 04-04 as the spike-findings record + open a new plan slot. The spike is a complete unit of work; mixing it with persistence implementation in a single SUMMARY would muddle the canonical decision-record. The user's preference / plan-checker discretion wins.

## Self-Check

Verifying claims before declaring plan complete (per executor protocol §self_check).

**Files created:**
- `tests/uat/spike-a33-sw-persistence.ts` — **FOUND** (verified via Read tool at session start; confirmed committed at 3726eee)
- `.planning/phases/04-harden-clean-up-optional/04-04-SUMMARY.md` — **FOUND** (this file, just written)

**Files modified:**
- `tests/uat/lib/harness-page-driver.ts` — **FOUND** (git diff verified pre-commit; helper landed at lines 49-80; findLatestZip exported at line 1434; committed at 3726eee)

**Commits:**
- `3726eee` (feat(04-04): Wave 0 spike — stopServiceWorker helper + 5-min SW idle empirical result) — **FOUND** in `git log --oneline -3`.

**Verification gates:**
- npx tsc --noEmit: exits 0 (verified pre-spike)
- HEADLESS=1 tsx tests/uat/spike-a33-sw-persistence.ts: ran to completion with explicit SPIKE RESULT + SPIKE OUTCOME lines + exit code 1 (FAILED branch — captured in /tmp/04-04-spike.log)
- npx tsc --noEmit (post-spike): exits 0 (helper + spike script both type-check cleanly; verified via the spike's tsc-clean exit before launch)
- Pre-checkpoint bundle gates: 6/6 GREEN unchanged from Plan 04-03 baseline (verified above)
- vitest baseline: 183 tests total; 3 pre-existing parallel-vitest flakes observed (out of scope per 04-CONTEXT items 9-10; pass in isolation; no regression caused by Plan 04-04 which made zero source-code changes)
- Spike acceptance criteria (Task 1):
  - `stopServiceWorker(browser, extensionId)` exists at tests/uat/lib/harness-page-driver.ts with canonical signature — **MET**
  - Spike script ran to completion (no Puppeteer throw) — **MET**
  - Spike result logged with explicit `videoSize=<N> bytes` line — **MET** (`videoSize=8505 bytes`)
  - SAVE_ARCHIVE dispatch uses `chrome.runtime.sendMessage` not `dispatchSaveArchive` — **MET** (grep verified: 0 hits on `dispatchSaveArchive`; 1 hit on `type: 'SAVE_ARCHIVE'`)
  - Spike outcome decision recorded (>100_000 → PASSED; ≤100_000 → FAILED) — **MET** (FAILED branch; SUMMARY documents failure mode + flag for re-planning per Task 1 acceptance criteria sentence)
- Task 2 acceptance criteria: **NOT APPLICABLE — Task 2 BLOCKED by gating condition (videoSize > 100_000 NOT met).**

## Self-Check: PASSED

All claims verified. Plan 04-04 closes at Task 1 (Wave 0 SPIKE FAILED) per the spike-first contract; Task 2 BLOCKED; ROADMAP SC #1 remains OPEN; plan-fix ceremony route documented.

---

## Post-Debug Amendment (2026-05-22)

The above SPIKE FAILED interpretation ("architecture broken → IndexedDB plan-fix needed") is **empirically REFUTED** by the follow-on `/gsd-debug` ceremony at `.planning/debug/sw-offscreen-persistence-investigation-session-2.md` (commit `4ea1bbb`). Per user-authorized ceremony route, the SC#1 routing was held until disambiguation completed.

**Session-2 verdict: REFUTED-architecture (canvas-captureStream issue).** The current `let segments: Blob[] = []` offscreen-RAM architecture (recorder.ts:91) is **NOT broken**. The spike's test methodology is invalid:

- **Pre-kill probe:** `segments.length=3` → segments accumulated correctly during the 5-min idle.
- **Post-kill probe:** `segments.length=3` → segments **survive** SW kill structurally (offscreen-RAM persistence works).
- **Step C (no SW kill, just 5-min idle + SAVE_ARCHIVE):** identical 8505-byte failure → Puppeteer `worker.close()` is **not the cause**; 5-min idle alone is what breaks the recording.
- **Direct Remux logs (visible in Step C because SW respawn did not happen):** `Segment ts=1..3: 0 frames, duration=0ms, trackInfo=320x180`; `Remux complete: 0 frames, total timeline=0ms, output=8505 bytes`.

**Root cause:** `installFakeDisplayMedia()` at `src/test-hooks/offscreen-hooks.ts:139-264` mints a `canvas.captureStream(30)` from a hidden -9999px-offset 320x180 canvas. Despite the `setInterval(drawFrame, 33ms)` belt-and-suspenders mitigation against RAF throttling, headless-Chromium aggressively throttles MediaRecorder on invisible-canvas sources (Chrome bug 653548; chromium auto-throttled-screen-capture design doc; sendrec.eu "Why Canvas Breaks Your Screen Recorder"). The MediaRecorder emits structurally-valid WebM with valid V_VP9 track metadata (320x180) but **zero VP9 frames per segment** over the 5-min idle window. The Remuxer correctly emits an 8505-byte header-only WebM from 3 × 0-frame segments.

**Reproducibility:** 7/7 spike runs across both debug sessions converge on identical 8505 bytes (deterministic methodology failure).

**Status correction (supersedes the above):**
- ROADMAP SC #1 remains **OPEN** but for a **TEST METHODOLOGY** reason — NOT for an architectural reason.
- The IndexedDB persistence plan-fix recommendation is **REJECTED**. It would not have closed SC#1 because the spike would still produce 8505 bytes after IDB lands; segments are not the problem, frames are.
- The correct fix: replace `canvas.captureStream(30)` in `installFakeDisplayMedia()` with an `HTMLVideoElement` playing a bundled WebM (Option 2 from session-2 recommendations). Bypasses canvas throttling entirely.

**Routing decision (user-authorized 2026-05-22):** Insert new **Plan 04-08** — video-file-backed MediaStream methodology reframe (replaces canvas.captureStream + revives the A33 harness assertion under a valid methodology). Plan 04-08 lands between Plans 04-06 and 04-07 (Wave 5.5).

**Persisting artifacts from this plan remain valid:**
- `stopServiceWorker(browser, extensionId)` at tests/uat/lib/harness-page-driver.ts — still required for the A33-equivalent verification gate that Plan 04-08 lands.
- `tests/uat/spike-a33-sw-persistence.ts` — kept as forensic evidence + future regression test (Plan 04-08 may reuse or supersede).
- Session-2 commit `9ac5808` — race-tolerant offscreen target attach fix at tests/uat/lib/launch.ts:225 (background_page → page, with full settle-and-retry). Permanent test-infra improvement; lives on past this plan.

---
*Phase: 04-harden-clean-up-optional*
*Plan: 04 (of 7, plus inserted 04-08)*
*Completed: 2026-05-21*
*Amended: 2026-05-22 — post-debug session-2 verdict REFUTED-architecture; SC#1 reframed to test-methodology issue; Plan 04-08 inserted*
*Outcome: SPIKE FAILED but root cause is test methodology (canvas throttling), not architecture; Plan 04-08 lands video-file MediaStream + A33 revival*
