---
status: testing
phase: 01-stabilize-video-pipeline
source:
  - 01-01-SUMMARY.md
  - 01-02-SUMMARY.md
  - 01-03-SUMMARY.md
  - 01-04-SUMMARY.md
  - 01-05-SUMMARY.md
  - 01-06-SUMMARY.md
  - 01-07-SUMMARY.md
verifier_residue: 01-VERIFICATION.md (status: human_needed, OPR-1/2/3)
debug_session_landed: .planning/debug/resolved/empty-archive-port-race.md (Option C — 8 commits 674c415..f0871c0)
started: 2026-05-16T11:14:00Z
updated: 2026-05-16T16:50:00Z
resumed_for: empirical re-verification of Option C fix (silent empty-video archive + port-reconnect race) before closing Phase 1
---

## Current Test

number: 3
name: "OPR-2: Continuous Recording Across Tab Switches (re-attempt post-Option-C)"
expected: |
  Now that Option C landed (port lifecycle refactor + request-id'd BUFFER
  routing + EmptyVideoBufferError surfaced to popup), Test 3 should now
  produce a zip with a valid `video/last_30sec.webm` AND show NO
  Uncaught Errors after the 290s mark (that timer is retired in favor
  of the port-health-probe). Re-run smoke.sh with the freshly built
  dist/ and confirm:
  (a) Recording runs uninterrupted across tab switches (open 2-3 new
      tabs, switch between them for ~30 s).
  (b) NO `Uncaught Error: Attempting to use a disconnected port object`
      appears in offscreen console — even past the 290 s mark.
  (c) The save flow completes in reasonable time (< 5 s, NOT 600 s as
      before).
  (d) The produced zip contains `video/last_30sec.webm` of expected
      size (~1.5 MB for 30 s VP9 1024×768-ish).
  (e) The WebM plays continuously in Chrome (no freeze, no missing
      seconds across tab-switch moments).
awaiting: user response (smoke.sh output + zip contents)

## Tests

### 1. Cold Start Smoke Test
expected: |
  Run `KEEP_PROFILE=0 ./smoke.sh` from a clean state. Chrome opens with a
  fresh `/tmp/mokosh-smoke-profile`. You manually Load Unpacked the `dist/`
  directory. Extension icon appears in the toolbar. No red errors in the SW
  console. SW console shows `[Background] Service Worker initialized` and
  an `OFFSCREEN_READY` handshake message. No "Receiving end does not exist"
  errors. (This catches the bugs that only show on fresh start — orphan IDB
  cleanup, missing onMessage listener, port handshake race CR-02/CR-03.)
result: pass
evidence: |
  User pasted SW console logs from chrome://extensions → service worker:
  - Service Worker initialized + initializing (MV3 install + startup, both clean)
  - "Cleaned up orphaned VideoRecorderDB" — Plan 01-05 IDB hygiene fires
  - "Received message: REQUEST_PERMISSIONS" — popup → SW message routing OK
  - "Creating offscreen document at: chrome-extension://.../src/offscreen/index.html"
    — Plan 01-06 crxjs build output path matches manifest
  - "Offscreen port connected" — T-1-04 keepalive port host (CR-02 fix) live
  - "Received message: OFFSCREEN_READY" → "OFFSCREEN_READY received" → CR-03
    handshake fix verified: SW waits for READY before sending START_RECORDING
  - "Sending START_RECORDING to offscreen..." → "START_RECORDING sent successfully"
    → "Video recording started successfully"
  Zero errors. Zero "Receiving end does not exist". Critical handshake races
  (CR-02 + CR-03) confirmed fixed at runtime.

### 2. OPR-1: getDisplayMedia Picker + Stream Grant
expected: |
  In the same smoke.sh-launched Chrome, click the extension icon. Chrome's
  native screen-share picker appears. Because smoke.sh passes
  `--auto-select-desktop-capture-source="Mokosh Smoke Test"`, the picker
  auto-accepts the smoke tab — no manual pick needed. "Sharing your screen"
  banner appears at the top of the Chrome window. SW console shows
  `[Offscreen:Recorder] Stream created` (or equivalent). No errors from
  `getDisplayMedia` rejection.
result: pass
evidence: |
  SW console logs show end-to-end happy path with no errors:
  - "Received message: REQUEST_PERMISSIONS" (popup → SW, click registered)
  - "Starting video capture for tab 240122995: data:text/html,..."
    (smoke tab targeted as expected)
  - "Creating offscreen document at: chrome-extension://.../src/offscreen/index.html"
  - "Offscreen port connected" + "OFFSCREEN_READY received"
  - "Sending START_RECORDING to offscreen..." → "START_RECORDING sent successfully"
  - **"Video recording started successfully"** — this final log only fires if
    MediaRecorder.start() in the offscreen doc completed without throwing,
    which means getDisplayMedia resolved with a stream (i.e., picker
    auto-accepted, stream granted, codec assertion passed).
  Note: "[Offscreen:Recorder] Stream created" log lives in the offscreen
  page's DevTools console (separate context from SW DevTools); user only
  shared SW console output. The SW-side "Video recording started successfully"
  is the equivalent positive signal.

### 3. OPR-2: Continuous Recording Across Tab Switches
expected: |
  With recording active (after Test 2), open 2-3 NEW tabs and switch
  between them rapidly for ~30 seconds. Then click the extension icon
  → "Сохранить отчёт об ошибке". smoke.sh detects the new
  `session_report_*.zip` in ~/Downloads, runs ffprobe (exit 0 expected),
  stages the WebM to `/tmp/mokosh-last_30sec.webm`, and opens it in
  Chrome. The video plays continuously for the full ~30 s with no freeze,
  no black frames, no missing seconds across the tab-switch moments.
  (Under getDisplayMedia, the stream is screen-or-window-scoped — tab
  switches should NOT interrupt capture. This is the empirical confirmation
  of D-01/D-15 amended semantics.)
result: issue
reported: |
  Three layers of evidence collected during this test:

  (a) Operator UX observation: "if i open the new tab, it suggest to
      'share this tab instead'" — Chrome's tab-share affordance.
  (b) Console errors: 3× Uncaught Error: Attempting to use a disconnected
      port object at offscreen:1:4644, starting at the 290 s pre-emptive
      reconnect mark.
  (c) **Silent data loss in the produced archive** (discovered after
      Test 3 was paused — user completed the save and shared smoke.sh
      output): smoke.sh waited 600 s before detecting the new zip; once
      detected, smoke.sh reported `caution: filename not matched:
      video/last_30sec.webm`. Inspecting the zip
      (`session_report_2026-05-16_13-54-52.zip`, 88 254 bytes) confirms
      it contains rrweb/session.json (empty), logs/events.json (empty),
      screenshot.png, meta.json — **no video/ directory at all**.
severity: blocker
observed_evidence: |
  Pre-bug (the GOOD news):
  - 33+ segment rotations over ~6 minutes, "kept: 3/3" invariant holding
    in the OS:Recorder logs (D-13 restart-segments lifecycle live and
    healthy — sizes 472-799 KB per 10s segment)

  The actual bug chain (most severe → least severe):

  1. **SILENT VIDEO DATA LOSS on save** (BLOCKER — defeats phase goal):
     - Archive shipped with no video file. The phase's whole point is
       producing a playable last_30sec.webm — and the operator-facing
       save flow does NOT do that.
     - Root cause located by code reading (NOT a fix attempt) at
       `src/background/index.ts:346-352`:
         if (videoBufferResponse.segments.length > 0) {
           zip.file('video/last_30sec.webm', mergeVideoSegments(...));
         } else {
           logger.warn('✗ No video segments to add');  // ← we hit this branch
         }
       The else-branch ships an archive missing the video file entirely,
       with only a warn log. This is exactly the silent-failure mode the
       phase set out to fix.
     - Upstream proximate cause: REQUEST_BUFFER round-trip fails to
       deliver a non-empty BUFFER response. Hypothesised pathway:
       offscreen's encodeAndSendBuffer captures portAtRequest via the
       CR-01 guard (recorder.ts:534), then awaits base64 encoding; if
       the pre-emptive 290s reconnect lands during that await, the
       guard at recorder.ts:597-601 correctly refuses to post on the
       stale port BUT also doesn't retry on the fresh port. The SW
       per-request listener (background/index.ts:130-167) times out
       silently after BUFFER_FETCH_TIMEOUT_MS=2_000, sets
       videoBufferResponse.segments = [], proceeds to build the
       empty-video archive. The 600 s smoke.sh wait suggests the
       operator clicked save multiple times until one
       REQUEST_BUFFER round-trip happened to NOT collide with a
       reconnect window.

  2. **3× Uncaught Error after pre-emptive reconnect** (MAJOR — noise +
     symptom of #1):
     - Locus: `src/offscreen/recorder.ts:623-625` (ping interval) +
       :626-630 (pre-emptive setTimeout). The setInterval ping callback
       uses `keepalivePort?.postMessage({ type: 'PING' })` — optional
       chaining only catches null, not a connected-but-disconnecting
       Port. Microtask race between disconnect() at line 628 and the
       teardownPortTimers() in onDisconnect at line 618 allows a queued
       ping callback to execute against the now-disconnected port.
     - Spacing matches PORT_PING_MS=25_000 across the post-reconnect
       window (errors at 11:50:10, ~11:50:40, ~11:51:00).
     - Same disconnect race almost certainly contributes to bug #1 by
       leaking REQUEST_BUFFER / BUFFER on the dead port.

  3. **Operator-side foot-gun: "Share this tab instead"** (MINOR —
     Phase 5 hardening; documented separately as advisory gap):
     - Chrome's platform UX surfaces this button on every other tab
       when extension uses getDisplayMedia in tab-share mode.
     - Mitigation options: (a) operator guidance "pick Entire Screen",
       (b) nudge picker via `video: { displaySurface: 'monitor' }`
       constraint in the getDisplayMedia call.

### 4. OPR-3: SW Idle-Unload Survival
expected: |
  Start a new recording (run smoke.sh again with KEEP_PROFILE=1 to reuse
  the loaded extension; click icon to start recording). Let it record
  ~15 s. Then: open `chrome://extensions` → find Mokosh → click the
  "service worker" link → in the DevTools that opens, click "Force stop"
  on the SW. Wait 60 s (the SW should stay dead — no auto-revival). Click
  the extension icon → "Сохранить отчёт об ошибке". SW revives, OFFSCREEN_READY
  handshake re-establishes, archive downloads. Open the WebM in Chrome →
  video from BEFORE the Force Stop is present in the file. (Tests that
  the offscreen-document buffer survives SW unload — D-16/D-17 + CR-03
  hasDocument fix. This is the most fragile path; if it fails, the bug
  is likely in `getVideoBufferFromOffscreen` post-respawn or in the
  OFFSCREEN_READY handshake re-fire.)
result: blocked
blocked_by: other
reason: |
  Paused by user decision after Test 3 surfaced the port-reconnect
  uncaught-error finding. Routed to /gsd-debug. Test 4 deliberately not
  attempted yet because it would compound debug-session signal: SW
  Force-Stop triggers exactly the disconnect→reconnect path that's
  currently buggy. Re-run after debug fix lands to get a clean signal
  on the SW-survival contract.

## Summary

total: 4
passed: 2
issues: 2 (Test 3 confirmed BLOCKER × 2: empty-archive fixed by Option C → new finding: D-13 multi-EBML-concat plays only ~9 s in mpv AND Chrome)
pending: 0
skipped: 0
blocked: 2 (Test 3 retest after D-13 architectural fix; Test 4 SW Force-Stop deferred behind the same fix)
paused_for: /gsd-debug d13-multi-ebml-concat-unplayable — Phase 1 architectural finding

## Gaps

- truth: "When the operator clicks save, the produced archive contains
    a playable video/last_30sec.webm derived from the ring buffer's most
    recent 30 s. This is the entire goal of Phase 1; without it the
    phase is not delivered to operators regardless of structural correctness."
  status: failed
  reason: |
    User reported smoke.sh waited 600 s then detected the new zip with
    `caution: filename not matched: video/last_30sec.webm`. Inspection:
    archive `session_report_2026-05-16_13-54-52.zip` (88 254 bytes)
    contains rrweb/session.json, logs/events.json, screenshot.png,
    meta.json — NO video/ directory. Code at
    src/background/index.ts:346-352 ships the archive without video
    when `videoBufferResponse.segments.length === 0`, only logging a
    warning. The empty-segments condition is reached when the
    REQUEST_BUFFER → BUFFER port round-trip fails. Three concrete
    failure modes contribute:
    (1) Pre-emptive 290 s reconnect race in offscreen recorder leaves
        encodeAndSendBuffer's portAtRequest stale; CR-01 guard at
        recorder.ts:597-601 correctly refuses to post BUFFER on dead
        port but doesn't retry on fresh port; SW listener times out
        silently after BUFFER_FETCH_TIMEOUT_MS=2_000.
    (2) Ping setInterval at recorder.ts:623-625 surfaces 3× Uncaught
        Error post-reconnect from the same race window — symptomatic
        of the same root cause.
    (3) saveArchive at background/index.ts:340+ has no retry-with-
        backoff on empty BUFFER and no operator-visible error signal —
        ships silently.
  severity: blocker
  test: 3
  artifacts:
    - path: src/background/index.ts
      lines: "346-352, 430-493, 130-167"
      issue: "Empty videoBufferResponse.segments silently produces no-video archive; saveArchive has no retry/error-surface; per-request BUFFER listener times out without retry"
    - path: src/offscreen/recorder.ts
      lines: "522-545, 597-604, 606-630, 623-625"
      issue: "Pre-emptive 290 s reconnect race window: encodeAndSendBuffer correctly drops stale post but never re-encodes/re-posts on fresh port; ping setInterval racing with reconnect's teardownPortTimers leaves callbacks executing on disconnected port"
  missing:
    - "REQUEST_BUFFER retry path on offscreen side after port reconnect (re-encode + re-post on fresh port)"
    - "OR: saveArchive-side retry loop with backoff when videoBufferResponse.segments is empty"
    - "Operator-visible error: surface 'no video data — try again' in popup instead of silently shipping no-video archive"
    - "Atomic ping-callback guard (check port.connected before postMessage, or try/catch)"
    - "Test coverage in tests/offscreen/port.test.ts: pre-emptive reconnect during in-flight REQUEST_BUFFER (currently only SW-side disconnect is pinned)"
    - "Test coverage in tests/background/: saveArchive behavior under empty-BUFFER response (currently no test exists for this branch)"
  debug_session: ""

- truth: "Operator picking 'tab' at the getDisplayMedia picker should not
    be one click away from accidentally redirecting the share target via
    Chrome's 'Share this tab instead' affordance."
  status: advisory
  reason: |
    Chrome's platform UX: when an extension uses getDisplayMedia to share
    a tab, every other tab shows a 'Share this tab instead' button in the
    'Sharing your screen' banner. Clicking it replaces the underlying
    MediaStream, which our onUserStoppedSharing handler treats as
    end-of-session. User flagged this during Test 3.
  severity: minor
  test: 3
  artifacts:
    - path: src/offscreen/recorder.ts
      lines: "ref D-01/D-15 amended getDisplayMedia call"
      issue: "displaySurface preference not declared"
  missing:
    - "Optional: pass { video: { displaySurface: 'monitor' } } to nudge
       Chrome's picker toward screen-share by default"
    - "Operator documentation: 'pick Entire Screen, not This Tab'"
  debug_session: ""
  defer_to_phase: 5

