mokosh/.planning/phases/04-harden-clean-up-optional/04-08-CHECKER-iter-2.md

phase, plan, checker_iteration, checked_at, plan_commit, parent_iter1_commit, verdict, severity_summary, goal_backward_check, recommendation

phase	plan	checker_iteration	checked_at	plan_commit	parent_iter1_commit	verdict	severity_summary	goal_backward_check	recommendation
04-harden-clean-up-optional	08	2	2026-05-22T15:00:00Z	1f2eb2e	051813e	PASSED	blocker warning cosmetic-advisory 0 1 4	Plan 04-08 iter-2 addresses both BLOCKERs from iter-1 with concrete, codified solutions: BLOCKER 1 (Vite ?url WAR strategy) is resolved by pre-deciding an explicit web_accessible_resources entry for assets/*.webm in manifest.json (Option B from iter-1 remediation), with grep gates enforcing both the presence of the entry AND the inert-production invariant. BLOCKER 2 (eager-install contract) is resolved by preserving installFakeDisplayMedia() as SYNCHRONOUS with the SYNC phase doing DOM creation + monkey-patch + module-level Promise kickoff, deferring the lazy first-frame wait (canplay + .play()) into the fakeGetDisplayMedia closure (Option A from iter-1 remediation). The five WARNINGs all have codified, grep-gated remediations in the verify blocks. The three cosmetic advisories are addressed in the plan body. One new WARNING surfaced during iter-2 review (the optional --check-display-surface-only sub-gate references a spike script mode that does not exist yet — labeled as 'create one or skip' but the create path is poorly scoped); four new cosmetic-advisories were noted. None of these rise to the level of blocking the plan.	PROCEED to execution. Plan 04-08 iter-2 is execution-ready. The single iter-2 WARNING is a low-severity scope-clarity issue on an OPTIONAL sub-gate (executor can take the documented alternative — rely on full spike re-run); it does not prevent the plan from achieving SC #1 closure. Total iter-2 findings (1 WARNING + 4 cosmetic-advisories) are below the PASSED threshold of '≤3 WARNINGs of low severity'.

Plan 04-08 Pre-Execution Validation — Iter-2

Plan under review: .planning/phases/04-harden-clean-up-optional/04-08-PLAN.md @ commit 1f2eb2e

Parent iteration: iter-1 at commit 051813e (verdict: ITERATE-NEEDED; 2 BLOCKER + 5 WARNING + 3 cosmetic-advisory)

Diff size (iter-1 → iter-2): +740 / -236 lines (planner re-drafted Task 1 Step 3 substantially + expanded both verify blocks + added revision_history + must_haves entries + STRIDE threats)

Authority artifacts re-read for iter-2:

• .planning/phases/04-harden-clean-up-optional/04-08-PLAN.md @ 1f2eb2e (1307 lines)
• .planning/phases/04-harden-clean-up-optional/04-08-CHECKER-iter-1.md @ 051813e
• .planning/phases/04-harden-clean-up-optional/04-04-PLAN.md (476 lines)
• .planning/phases/04-harden-clean-up-optional/04-04-SUMMARY.md (267 lines + amendment)
• .planning/debug/sw-offscreen-persistence-investigation-session-2.md (97 lines)
• .planning/phases/04-harden-clean-up-optional/04-CONTEXT.md
• .planning/PROJECT.md + .planning/ROADMAP.md (lines 240-292)
• src/test-hooks/offscreen-hooks.ts (full 541 lines)
• src/offscreen/recorder.ts:40-100 (top-level await + segments declaration)
• tests/uat/spike-a33-sw-persistence.ts (full 337 lines)
• tests/uat/lib/harness-page-driver.ts:40-130 (Browser type + stopServiceWorker + interfaces)
• tests/uat/extension-page-harness.ts (assertA2 + setupFreshRecording location)
• tests/uat/harness.test.ts:95-138, 340-487 (imports + drivers-array + wrapped-driver block)
• globals.d.ts (37 lines)
• manifest.json (current source) + dist/manifest.json (current build output — KEY EMPIRICAL: shows crxjs DID auto-WAR JS chunks assets/logger-WoCoXGpL.js, assets/index-CgqXENQe.js, assets/index.ts-D0uUn23q.js — refining the iter-1 picture)
• vite.config.ts (170 lines) + vite.test.config.ts (101 lines)
• tests/background/no-test-hooks-in-prod-bundle.test.ts (297 lines — full Tier-1 inventory + collectDistFiles helper structure)
• dist/ + dist-test/ file enumeration (verified zero *.webm in either currently; dist-test/assets/offscreen-hooks-BvgUCNzF.js present)
• tests/fixtures/last_30sec.webm (1888636 bytes; codec=vp9; width=1142; height=1044; duration=N/A per ffprobe — same as iter-1)
• tests/uat/fixtures/ directory: DOES NOT EXIST YET — confirms Task 1 Step 1 still needs to land the directory + file

---

Goal-Backward Verification — Iter-2 Still Closes SC #1?

Architectural claim (unchanged from iter-1): HTMLVideoElement.captureStream bypasses canvas-throttling per debug session-2; segments architecture preserved.

Iter-2 reinforcement: the SYNC-install + LAZY-first-frame contract is now codified with three independent grep gates in Task 1 verify:

1. grep -c "installFakeDisplayMedia(): void" ≥ 1 (sync signature)
2. grep -c "export function installFakeDisplayMedia(): Promise" == 0 (NOT async — negation gate)
3. grep -c "await installFakeDisplayMedia" == 0 (no callers turned async — bridge + eager-install preserved)

These three gates collectively make BLOCKER 2's race condition unreintroducible without tripping the build. The verification is mechanical, not judgment-based.

Verdict: YES — Plan 04-08 iter-2 IS execution-ready. Both blockers from iter-1 have concrete, codified, grep-gated remediations. The single new WARNING (below) is a scope-clarity issue on an optional sub-gate, not a blocker.

---

Iter-1 BLOCKER Resolution Verification

BLOCKER 1 (Vite ?url asset-emission path) — ADDRESSED

Iter-1 finding: the ?url import for a 1.9 MB WebM is the extracted-asset code path (different from Plan 01-10 mokosh-mark.svg's 877-byte inlined SVG path); the @crxjs/vite-plugin auto-WAR behavior for extracted-media-assets in offscreen-document context was unverified; the plan's contingency block delegated the decision to executor improvisation.

Iter-2 resolution (verified):

• Strategy chosen: Option B from iter-1 remediation (explicit web_accessible_resources entry for assets/*.webm in manifest.json). Plan lines 86-92, 407-419, 894-913 + must_haves.artifacts entry for manifest.json + key_links entry + STRIDE T-04-08-09 (regression catch).
• Pre-decided, not delegated: the plan explicitly states (line 908) "Rationale (locked in iter-2; no executor decision)". The pre-edit manifest excerpt + post-edit JSON are both shown verbatim in the <interfaces> block (lines 397-419). No "executor decides at run time" ambiguity remains.
• Empirical justification: Plan correctly states (line 911) that the WAR entry "is inert in production" because find dist -name '*.webm' | wc -l == 0 (verified live: confirmed; the current production dist/ has zero *.webm files).
• Grep gates:
  • Task 1 verify: grep -c '"assets/\*\.webm"' manifest.json | awk '$1 >= 1 {exit 0} {exit 1}'
  • Task 1 verify: find dist -name '*.webm' | wc -l | awk '$1 == 0 {exit 0} {exit 1}' (production inert)
  • Task 1 verify: find dist-test -name '*.webm' | wc -l | awk '$1 >= 1 {exit 0} {exit 1}' (test bundle authoritative)
  • Task 1 verify: grep -r "synthetic-display-source" dist/ 2>/dev/null | wc -l | awk '$1 == 0 {exit 0} {exit 1}' (no production leak)

Iter-2 verification observation refining iter-1's picture: examining the current dist/manifest.json empirically shows that @crxjs/vite-plugin DID auto-WAR three JS chunks (assets/logger-WoCoXGpL.js, assets/index-CgqXENQe.js, assets/index.ts-D0uUn23q.js). So crxjs's auto-WAR behavior IS active for extracted JS assets transitively reachable from extension-page entrypoints. Whether it would auto-WAR a WebM asset transitively-reachable-from-the-offscreen-document is a slightly different question (the iter-2 plan correctly identifies offscreen documents as a different code path than typical extension pages). The defensive explicit entry remains the right call — it's cheap, idempotent with whatever crxjs may or may not auto-WAR, and it's empirically inert in production.

Verdict on BLOCKER 1: RESOLVED.

BLOCKER 2 (installFakeDisplayMedia() async conversion → race) — ADDRESSED

Iter-1 finding: the original plan's recommendation to convert installFakeDisplayMedia() to async + use void installFakeDisplayMedia().catch(...) at module load would create a race window where recorder.startRecording's await navigator.mediaDevices.getDisplayMedia(...) could see the REAL (un-patched) navigator.mediaDevices.getDisplayMedia and hang on the Chrome screen-share picker.

Iter-2 resolution (verified):

• Strategy chosen: Option A from iter-1 remediation (SYNC install + LAZY first-frame closure). Plan lines 220-335 in <interfaces> + lines 618-892 in Task 1 Step 3.
• SYNC contract preserved verbatim: installFakeDisplayMedia(): void — function signature unchanged from current code. The plan's Sub-step 3c explicitly says (line 620): "Critical contract: installFakeDisplayMedia() MUST remain SYNCHRONOUS (no async/await in the function declaration). ... DO NOT convert to async. DO NOT change the function's return type."
• SYNC phase work:
  • document.createElement('video') + setting all videoEl attrs (sync)
  • document.body.appendChild(videoEl) (sync)
  • fakeVideoEl = videoEl (sync module-level cell assignment)
  • fakeVideoReadyPromise = new Promise<void>((resolve, reject) => { ... }) (sync — Promise constructor returns immediately; the canplay listener is registered sync but does not yet fire)
  • videoEl.addEventListener('canplay', onCanPlay) + videoEl.addEventListener('error', onError) (sync registration)
  • (navigator.mediaDevices as ...).getDisplayMedia = fakeGetDisplayMedia (sync monkey-patch assignment — KEY GATE)
• LAZY phase work (inside fakeGetDisplayMedia closure):
  • await fakeVideoReadyPromise (waits for canplay + .play() resolution; first call may block ~50-500ms; subsequent calls observe resolved Promise immediately)
  • mintStream() → videoEl.captureStream(30) + patchDisplaySurface(stream) → return
• Eager-install at lines 528-537 UNCHANGED: plan's Sub-step 3f explicitly verifies the existing try { installFakeDisplayMedia(); } catch (e) {...} still works because the function remains sync void.
• Bridge handler at lines 408-418 UNCHANGED: plan's Sub-step 3g explicitly verifies the existing if (op === 'install-fake-display-media') { ... return false; } (sync sendResponse + return false) still works because the install itself stays sync.
• Three grep gates codify the contract (Task 1 verify block):
  • grep -c "installFakeDisplayMedia(): void" ≥ 1 (sync signature present)
  • grep -c "export function installFakeDisplayMedia(): Promise" == 0 (negation gate — explicitly verifies NOT async)
  • grep -c "await installFakeDisplayMedia" == 0 (negation gate — neither bridge handler nor eager-install await it)
• STRIDE threat T-04-08-08 explicitly codifies the regression-catch contract: "future refactor converts installFakeDisplayMedia() to async (breaking the eager-install contract — recurrence of iter-2 BLOCKER 2). Mitigate: Grep gate codified in Task 1 verify... Any future PR that flips the signature trips the build-test pipeline."

Race-window analysis: the iter-2 plan correctly identifies the head-start window — fakeVideoReadyPromise is kicked off at install time (sync), so by the time recorder.startRecording reaches await navigator.mediaDevices.getDisplayMedia(...) (which happens AFTER recorder.ts:46-48 top-level await resolves AND after recorder.bootstrap() AND after the production START_RECORDING handler dispatches), the video element has typically had hundreds of ms head start on its canplay event. The first invocation MAY block briefly inside the closure (~50-500ms per plan estimate); subsequent calls fast-path. This matches Option A from iter-1 remediation verbatim.

Verdict on BLOCKER 2: RESOLVED.

---

Iter-1 WARNING Resolution Verification

WARNING 1 (headless autoplay fallback) — ADDRESSED

Iter-1 finding: no fallback for videoEl.play() rejecting with NotAllowedError.

Iter-2 resolution: plan lines 289-295 + 711-728 — the Promise rejection path produces an explicit error class identifier:

reject(new Error(
  `synthetic-display-source.webm play() rejected: ${...} (autoplay-blocked or codec-unsupported in headless context)`
));

The error message includes the explicit class string (autoplay-blocked or codec-unsupported in headless context) so a downstream spike failure surfaces the precise root cause via the offscreen console capture (the existing harness diagnostic plumbing already captures offscreen.console). NOT a true "Plan B fallback" (no synthetic-user-gesture path; no canvas-fallback), but an EXPLICIT diagnostic signal so the failure mode is unambiguous.

Verdict: PARTIAL but acceptable. The iter-2 approach trades full fallback for explicit failure-mode signaling. Acceptable because (a) muted-autoplay in headless Chrome is well-established practice (numerous Chromium test suites rely on it); (b) the explicit error classification means a hostile failure surfaces in the spike re-run as an unambiguous signal rather than as a mysterious 0-frames result. NEW cosmetic-advisory below mentions one improvement.

WARNING 2 (displaySurface monkey-patch portability) — ADDRESSED

Iter-1 finding: patchDisplaySurface() was assumed to work with HTMLVideoElement.captureStream tracks; not verified.

Iter-2 resolution: plan Sub-step 3 Step 7 (lines 966-967) adds an explicit --check-display-surface-only sub-gate:

HEADLESS=1 SKIP_PROD_REBUILD=1 npx tsx tests/uat/spike-a33-sw-persistence.ts --check-display-surface-only 2>&1 | tee /tmp/04-08-display-surface-check.log

with documented expected log line DISPLAY-SURFACE-CHECK: PASSED. Implementation noted as "append to the existing tests/uat/spike-a33-sw-persistence.ts script a --check-display-surface-only mode that runs only Steps 1-2 (prime + 5s post-prime probe), invokes __mokoshOffscreenQuery op='get-display-surface', asserts result is 'monitor', exits."

Verdict: ADDRESSED but with a NEW concern — see "New iter-2 WARNING" below regarding the optional-vs-required ambiguity of this sub-gate.

WARNING 3 (spike probe-value grep gates) — ADDRESSED

Iter-1 finding: the three probe-value checks (POST-PRIME=0, PRE-KILL≥3, POST-KILL≥3) were buried in prose, not surfaced as automated grep gates.

Iter-2 resolution: Task 2 verify block contains explicit grep gates (line 1173):

grep -cE 'SPIKE PROBE \[POST-PRIME\]: segments\.length=0' /tmp/04-08-spike-rerun.log
grep -cE 'SPIKE PROBE \[PRE-KILL\]: segments\.length=([3-9]|[1-9][0-9]+)' /tmp/04-08-spike-rerun.log
grep -cE 'SPIKE PROBE \[POST-KILL\]: segments\.length=([3-9]|[1-9][0-9]+)' /tmp/04-08-spike-rerun.log

Cross-checked with the spike script (tests/uat/spike-a33-sw-persistence.ts:139-144 + 252): the script emits the exact label strings SPIKE PROBE [POST-PRIME], SPIKE PROBE [PRE-KILL], SPIKE PROBE [POST-KILL] (when canonical mode; POST-SKIP-KILL only when SPIKE_SKIP_SW_KILL=1, which the canonical re-run does NOT set). Regex patterns match the actual emit format.

Verdict: RESOLVED.

WARNING 4 (ROADMAP.md edit pre-spec + grep gate) — ADDRESSED

Iter-1 finding: the ROADMAP SC #1 flip was described inline without a grep gate to enforce the edit landed correctly.

Iter-2 resolution: plan Step 7 (lines 1118-1166) pre-specifies the EXACT pre-edit prose block + EXACT post-edit prose block (both shown verbatim) + adds 3 grep gates:

grep -c 'CLOSED via Plan 04-08' .planning/ROADMAP.md         # >= 1
grep -c 'STATUS 2026-05-21: OPEN' .planning/ROADMAP.md       # == 0 (old removed)
grep -c 'STATUS 2026-05-22: CLOSED' .planning/ROADMAP.md     # >= 1

Cross-checked with current ROADMAP.md (line 254): STATUS 2026-05-21: OPEN is indeed present verbatim. The pre-edit text shown in the plan's -equivalent block matches the actual ROADMAP.md text. Plan also pre-specifies the Plan tracker line update at ~line 277 + the phase tracker table row at ~line 292.

Verdict: RESOLVED.

WARNING 5 (Tier-2 filename-leak gate) — ADDRESSED

Iter-1 finding: the test-only synthetic-display-source.webm filename was not gated against accidental production-bundle leak.

Iter-2 resolution: plan Task 1 Step 6 (lines 919-948) adds a NEW Tier-2 sub-test in tests/background/no-test-hooks-in-prod-bundle.test.ts:

test('Tier-2: synthetic-display-source filename does not leak into production dist/', () => {
  const distFiles = collectDistFiles();
  const offendingFiles: string[] = [];
  for (const filePath of distFiles) {
    const content = readFileSync(filePath, 'utf-8');
    if (content.includes('synthetic-display-source')) {
      offendingFiles.push(filePath);
    }
  }
  expect(offendingFiles).toEqual([]);
});

Plan also notes (line 950): "the executor should READ the existing test file first to identify the exact name of the helper that walks dist/ files (the snippet above calls it collectDistFiles — verify the actual name and adapt)."

Cross-check with actual test file: the actual helper at tests/background/no-test-hooks-in-prod-bundle.test.ts:152-171 is named listAllFilesRecursive(DIST_DIR), NOT collectDistFiles. The plan acknowledges this ambiguity with its "verify the actual name and adapt" guidance. This is acceptable scope-of-discretion handoff — the executor reading the file first will substitute the correct symbol. NEW cosmetic-advisory below notes the executor could have been spared this lookup if the plan had stated the exact symbol name.

Verdict: RESOLVED (with minor advisory). Tier-1 inventory at 12 unchanged confirmed; Tier-2 is a new orthogonal axis (asset filenames) not in the lockstep.

---

Iter-1 Cosmetic-Advisory Resolution Verification

advisory 1 (Task 3 reference in commit message) — ADDRESSED

Plan Step 8 (line 1168): "Single atomic commit for Task 2 with all Task 2 artifacts + SUMMARY + STATE/ROADMAP markers: feat(04-08): A33 SW state persistence harness assertion — methodology reframe (34/34 GREEN; ROADMAP SC #1 CLOSED). Task 1 was committed separately at the close of Task 1 per its own done line: feat(04-08): video-file MediaStream + sync-install/lazy-first-frame + explicit WAR — methodology reframe per debug session-2 + iter-2 BLOCKER fixes." — correctly references Task 1 + Task 2 only (no Task 3).

Verdict: RESOLVED.

advisory 2 (segments invariant grep) — ADDRESSED

Plan Task 1 Step 7 + verify (line 968): grep -cE 'let segments: Blob\[\] = \[\];' src/offscreen/recorder.ts returns 1.

Verdict: RESOLVED.

advisory 3 (dual-fixture-location note) — ADDRESSED

Plan Task 1 Step 1 (line 601): "advisory 3 note: tests/fixtures/last_30sec.webm remains in place (Plan 01-07 regression fixture; not affected). The new path at tests/uat/fixtures/synthetic-display-source.webm is a SECOND copy under the UAT subtree..." + further rationale.

Verdict: RESOLVED.

---

NEW Iter-2 Findings

NEW WARNING (single, low-severity) — displaySurface sub-gate scope ambiguity

Dimension: task_completeness

Plan claim (lines 966-967, Task 1 Step 7):

The plan introduces an explicit --check-display-surface-only mode for the spike script as the WARNING 2 remediation. The mode does not exist yet in tests/uat/spike-a33-sw-persistence.ts (verified empirically — grep returns 0 hits on --check-display-surface-only or DISPLAY-SURFACE-CHECK). The plan delegates the implementation to "append to the existing tests/uat/spike-a33-sw-persistence.ts script a --check-display-surface-only mode that runs only Steps 1-2 (prime + 5s post-prime probe)" without specifying the exact entry-point change, the exact log emit format, or whether the spike script's existing process.exit(code) at line 336 is short-circuited in this mode.

Plan ALSO offers an explicit alternative (line 967): "Alternative if the executor finds the spike-script-augmentation overhead too high: skip the dedicated sub-gate and rely on the spike re-run in Task 2 Step 1 (the displaySurface failure would manifest as 'wrong-display-surface' Error in the offscreen console capture; the spike's gating condition would still fail). The dedicated sub-gate is the LOW-LATENCY path; the spike re-run is the HIGH-LATENCY path; both gate the same invariant."

Why this is a WARNING, not a BLOCKER:

• The alternative path is documented and well-reasoned — the spike re-run in Task 2 Step 1 DOES catch the same failure, just with 6+ min latency instead of <10s.
• Task 1's <verify> block does NOT currently include a grep 'DISPLAY-SURFACE-CHECK: PASSED' /tmp/04-08-display-surface-check.log gate (line 971 verify command does NOT include this grep), so the sub-gate is genuinely optional — Task 1 verification passes without it.
• The plan's STRIDE threat T-04-08-08 + the WARNING 2 remediation are not weakened by skipping the sub-gate, because the spike re-run is the canonical catch.

Why it's still a WARNING:

• The "create a new spike-script mode" path is under-specified relative to the rest of the plan. An executor who chooses the LOW-LATENCY path would be making 5-10 LOC of implementation decisions (where to insert the env-var check; what to log; whether to wire it through main() or a new mainCheckDisplaySurface(); what process.exit code to use) that the plan does not pre-specify.
• The plan would be tighter if the displaySurface sub-gate were either (a) fully spec'd (5-10 lines of the exact code to add to the spike script) OR (b) explicitly retired in favor of the high-latency alternative (with a note in the SUMMARY documenting the WARNING 2 closure path was the high-latency one).

Remediation for iter-3 (NOT NEEDED — does not block execution):

Either pre-spec the exact spike-script edit (concrete 5-10 LOC patch), OR explicitly retire the sub-gate option (single sentence: "executor takes the HIGH-LATENCY path via Task 2 Step 1 spike re-run; the dedicated sub-gate is dropped"). Both fixes are <5 lines of plan text.

Severity: WARNING (not BLOCKER). The alternative path is documented; SC #1 closure is not impacted.

NEW cosmetic-advisory 1 — collectDistFiles symbol-name mismatch

Plan line 939: const distFiles = collectDistFiles(); // existing helper from the Tier-1 test

Actual code: the helper at tests/background/no-test-hooks-in-prod-bundle.test.ts:152 is named listAllFilesRecursive(DIST_DIR).

The plan's own note at line 950 says "verify the actual name and adapt" — so the executor's lookup is anticipated and acceptable, but the plan would be tighter if the correct symbol name (listAllFilesRecursive) were used directly in the snippet. Cosmetic; ~30 seconds of executor lookup time saved.

NEW cosmetic-advisory 2 — WARNING 1 documentation could be slightly stronger

The plan's WARNING 1 resolution (lines 711-728) trades a true fallback for explicit error classification. The SUMMARY (per Step 6's expected content list at lines 1109) does not explicitly call out "WARNING 1 closure path: no fallback; explicit error classification chosen instead" — the executor writing the SUMMARY should be careful to acknowledge the trade-off. This is a meta-note about SUMMARY-writing practice, not a plan-edit need.

NEW cosmetic-advisory 3 — vitest baseline numbers minor inconsistency

Plan line 1100: "vitest baseline preserved: npm test 2>&1 | tail -5 — expect 184/184 GREEN (was 183 baseline + 1 new Tier-2 test from Plan 04-08)"

Plan line 1261: "vitest baseline 184 preserved (183 prior + 1 new Tier-2; or 181/184 with 3 documented pre-existing flakes; pass in isolation)"

Both correct, but the math 183 + 1 = 184 should be flagged: 1 new Tier-2 test adds 1 test to the inventory, but the prior baseline (per 04-04-SUMMARY) was 183. Verify: npm test baseline is currently 183/183 GREEN absent the new Tier-2 test; after Plan 04-08 it becomes 184/184. Math checks out; cosmetic.

NEW cosmetic-advisory 4 — duration-N/A acknowledged but not load-bearing

Plan Task 1 Step 1 (line 600): "duration is N/A per ffprobe (live-capture WebM lacks a duration tag), BUT the 1.9 MB VP9 at 400 kbps yields ~38s of decoded timeline — sufficient for the 5-min spike via videoEl.loop = true."

Empirically verified: ffprobe ... tests/fixtures/last_30sec.webm reports duration=N/A, codec=vp9, 1142x1044. The plan's claim about ~38s decoded timeline is reasonable (1888636 bytes / 400kbit/s ≈ ~38s). The videoEl.loop = true attr handles indefinite playback. This is a minor reasoning chain that's worth pinning explicitly in the SUMMARY's "Bundled WebM fixture decision" section so future maintainers understand why the N/A duration is acceptable. Cosmetic.

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Dimensional Pass/Fail Summary

Dimension	Status	Notes
1. Requirement Coverage	PASS	Phase requirements honor D-P4-01 (Full Phase 4 — ROADMAP SC #1); tasks address SC #1 directly.
2. Task Completeness	PASS	Both tasks have all 4 elements; iter-2 added codified grep gates in both verify blocks; only the displaySurface sub-gate has the scope ambiguity noted above.
3. Dependency Correctness	PASS	depends_on [01,02,03,04,05,06] is acyclic + correct (Wave 5.5 after Wave 5).
4. Key Links Planned	PASS	iter-2 codifies the WAR entry + the sync-monkey-patch chain. key_links section is explicit about the chrome-extension://-scheme route + the lazy-first-frame closure.
5. Scope Sanity	PASS	2 tasks; 10 files_modified (was 7 in iter-1; iter-2 added globals.d.ts, manifest.json, tests/background/no-test-hooks-in-prod-bundle.test.ts). Within the 2-3 task / 5-8 file target's flexibility budget; the additions are small and well-scoped.
6. Verification Derivation	PASS	must_haves.truths are user-observable (videoSize > 100_000, 34/34 GREEN, ROADMAP SC #1 CLOSED); iter-2 added 4 new truths (lines 61-62, 65, 73, 76 — sync-install/lazy-closure, WAR entry, Tier-2 gate, patchDisplaySurface compatibility).
7. Context Compliance	PASS	Honors D-P4-01 (full scope); does not contradict locked decisions; deferred IDB persistence work correctly excluded per debug session-2 verdict.
7b. Scope Reduction Detection	PASS	No "v1"/"static for now"/"future enhancement" language; plan delivers SC #1 fully. iter-2 actually EXPANDS scope (adds Tier-2 gate, WAR entry, displaySurface sub-gate, 4 new must_haves truths) — opposite of reduction.
7c. Architectural Tier Compliance	PASS	Test-only hook (test-hooks tier) + bundled test asset (fixtures tier) + Tier-2 gate (test build verification tier) are all correctly tier-located. Production code untouched.
8. Nyquist Compliance	PASS	Both tasks have <automated> verify commands; Task 1 build-test verify + 14 separate grep gates + 1 vitest sub-test; Task 2 UAT skip-mode verify + 5 separate grep gates including the WARNING 3 probe values. No watch-mode; sampling adequate.
9. Cross-Plan Data Contracts	PASS	No competing transforms on shared data; offscreen RAM buffer pipeline unchanged.
10. CLAUDE.md Compliance	N/A	No ./CLAUDE.md exists in working directory. Skip per protocol.
11. Research Resolution	PASS	04-RESEARCH.md Q2 was resolved + superseded by debug session-2; plan explicitly references the supersession + amends Plan 04-04 SUMMARY.
12. Pattern Compliance	PASS	iter-2 explicitly clarifies that Plan 01-10 mokosh-mark.svg is the SVG-side analog (different code path due to inline limit) + that the explicit WAR entry is the iter-2 BLOCKER 1 remediation. The pattern analog is appropriately scoped.

---

Recommendation for Orchestrator

Verdict: PASSED.

Plan 04-08 iter-2 is execution-ready. Both iter-1 BLOCKERs have concrete, codified, grep-gated remediations. All five WARNINGs are addressed. All three cosmetic-advisories are addressed. One new WARNING and four new cosmetic-advisories were surfaced during iter-2 review, but none rise to the level of blocking execution:

• NEW WARNING (displaySurface sub-gate scope): the optional --check-display-surface-only mode is under-spec'd, but the plan documents an explicit alternative (high-latency catch via spike re-run). Executor can take either path; SC #1 closure is not impacted.
• NEW cosmetic-advisories (4): symbol-name mismatch, SUMMARY-write practice note, vitest math note, duration-N/A rationale. All minor.

Iter-2 findings (1 WARNING + 4 cosmetic-advisories) are below the PASSED threshold of "≤3 WARNINGs of low severity". The single WARNING is genuinely low-severity (alternative documented; not a blocker).

Proceed to execute Plan 04-08. Wave 5.5 starts with Task 1 (bundle + WAR entry + sync-install/lazy-closure rewrite + Tier-2 gate); Task 2 follows (spike re-run + A33 land + ROADMAP flip).

Architectural alignment confirmed (carried forward from iter-1 + reinforced in iter-2): the plan's core thesis (HTMLVideoElement.captureStream bypasses canvas-throttling per debug session-2) is correct. The iter-2 revision tightens both the bundling-strategy decision AND the sync-monkey-patch contract with explicit codified gates. Execution-ready.

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Plan-checker iter-2 completed 2026-05-22 by gsd-plan-checker. Output committed atomically; orchestrator decides routing (execute Plan 04-08 OR optional iter-3 to address the displaySurface sub-gate scope WARNING).