- F5 [stability/regression]: the round-1 F2 fix re-rendered the root with
<PostHogProvider><App/></PostHogProvider> after the analytics chunk loaded. In
the ChunkLoadErrorBoundary child slot the element TYPE changes App ->
PostHogProvider, so React does NOT reconcile in place — it REMOUNTS the whole
App: every mount effect runs twice (websocket connect/disconnect, origin
tracking, subscriptions) and local state / focus / scroll / in-progress input is
lost on cloud cold-load (e.g. typing in /login before analytics loads). And it
was USELESS: the app has ZERO consumers of the PostHog React context (no
usePostHog / useFeatureFlag* / PostHogFeature), and PostHogProvider given an
initialized client is a no-op — all capture goes through the posthog singleton.
Fix: initAnalytics now inits the posthog SINGLETON only (no posthog-js/react
import, no second render); renderApp() renders <App/> once. First paint stays
instant, cloud analytics behavior unchanged, no remount.
- F6 [test]: exported isChunkLoadError + chunk-load-error-boundary.test.ts —
pins the detector (ChunkLoadError name + the 3 dynamic-import failure messages,
case-insensitive → true; null/undefined/ordinary errors → false) so a
false-negative that re-blanks the app on a real chunk-404 is caught.
Gate: client tsc 0, chunk-load + sanitize tests 14 passed. Entry chunk unchanged.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
- F1 [HIGH]: added a root ChunkLoadErrorBoundary (react-error-boundary) wrapping
the routed app in main.tsx, ABOVE all the route-level/Aside/AiChatWindow
Suspense boundaries. A stale-deploy chunk 404 (React.lazy reject) is caught and
auto-reloads once (sessionStorage-guarded against a reload loop), else shows a
manual "new version available" reload UI — instead of unmounting the whole tree
to a white screen. Existing per-feature ErrorBoundaries untouched.
- F2 [MED-HIGH]: posthog no longer blocks/blanks the cloud first paint. main.tsx
now renders <App/> immediately for everyone, then `void initAnalytics()` — which
keeps the exact cloud gate, dynamically imports posthog, and RE-RENDERS the same
React root wrapped in PostHogProvider (React reconciles onto the painted DOM, so
cloud ends up wrapped exactly as before). The import+init is try/catch'd: a
failed analytics chunk (network / stale-404 / ad-blocker on a "posthog" chunk)
degrades to no-analytics instead of a permanently blank page.
- F3: sanitize-url.test.ts mirroring editor-ext's security contract (javascript:/
data:/vbscript:/obfuscated → ""; https/relative/mailto preserved).
- F4: the idle-warm `void import(...)` prefetch in layout.tsx gets `.catch(()=>{})`
so a failed best-effort prefetch can't surface as an unhandledrejection.
No new deps (lockfile unchanged). Gate: client tsc 0, sanitize test 3/3, client
build succeeds (entry chunk still 556K, posthog in separate dynamic chunks).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
agent_coder