speed up feeds by leaning more into NostrArchive API

add a picture button to image fallbacks

docs/performance-fixes.md

@@ -0,0 +1,182 @@
+# Performance fixes (audit follow-up)
+
+This document records seven fixes identified during a sluggishness audit. They are ordered by impact and should be applied in sequence.
+
+## Executive summary
+
+Sluggishness came mainly from **main-thread work that scales with feed size** and **React context churn** that re-renders large subtrees. Orphaned files added maintenance noise but did not affect runtime.
+
+The largest win is in `NoteList`: expensive per-event work ran inside a filter that scans up to **2,500 events** on every dependency change.
+
+---
+
+## Fix 1 — Hoist `pinnedEventHexIdSet` out of `shouldHideEvent`
+
+**File:** `src/components/NoteList/index.tsx`
+
+**Problem:** `shouldHideEvent` rebuilt `pinnedEventHexIdSet` (with `decode()` per pin) **inside** the per-event callback. That callback is used in a `useMemo` that scans up to `MAX_TIMELINE_EVENTS_SCAN_FOR_VISIBLE` (2500) rows, so pin decoding ran up to 2,500× per filter pass.
+
+**Fix:** Compute `pinnedEventHexIdSet` once in a `useMemo` keyed on `pinnedEventIds`. `shouldHideEvent` reads the memoized set.
+
+**Expected impact:** Largest feed-filter win; small diff.
+
+---
+
+## Fix 2 — Cap profile-prefetch walks to visible + lookahead
+
+**File:** `src/components/NoteList/index.tsx`
+
+**Problem:** A debounced `useEffect` walked **all** of `timelineEventsForFilter` and `newEvents` on every buffer change, then enqueued profile/emoji prefetch for every author found.
+
+**Fix:** Walk only `filteredEvents.slice(0, showCount + prefetchMargin)` (capped, e.g. 120 rows) plus a small slice of `newEvents` (e.g. 32). Keep the existing note-stats slice for visible rows.
+
+**Expected impact:** Fewer redundant kind-0 fetches and less main-thread work when the timeline buffer grows.
+
+---
+
+## Fix 3 — Memoize `MuteListProvider` and `ContentPolicyProvider` context values
+
+**Files:**
+- `src/providers/MuteListProvider.tsx`
+- `src/providers/ContentPolicyProvider.tsx`
+
+**Problem:** Both providers passed a new `value` object every render. Handler functions were recreated each render. Consumers include `NoteList`, `Note`, `Image`, `VideoPlayer`, etc., so parent re-renders cascaded through the feed.
+
+**Fix:**
+- Wrap mute handlers in `useCallback`.
+- Wrap policy updaters in `useCallback`.
+- Wrap provider `value` in `useMemo` with stable dependencies.
+
+**Expected impact:** Fewer wide subtree re-renders when unrelated parent state changes.
+
+---
+
+## Fix 4 — Cap `iterateProfileEvents` IndexedDB scan
+
+**File:** `src/services/indexed-db.service.ts`
+
+**Problem:** `iterateProfileEvents` loaded **all** kind-0 rows from IndexedDB into a single `events[]` array before chunked callback processing. Large offline caches caused a big allocation on first @-mention search or session prewarm.
+
+**Fix:** Cap rows collected during the cursor pass (`MAX_PROFILE_EVENTS_ITERATE`, e.g. 8,000). Log when truncated. Keep chunked `requestAnimationFrame` yields during callback processing.
+
+**Expected impact:** Bounded memory and faster startup on accounts with very large profile caches.
+
+---
+
+## Fix 5 — Tune `ReplaceableEventService` batching during scroll
+
+**Files:**
+- `src/lib/scroll-activity.service.ts` (new)
+- `src/components/NoteList/index.tsx`
+- `src/services/client-replaceable-events.service.ts`
+
+**Problem:** `maxBatchSize: 200` with 100ms batching queued many kind-0 fetches during fast scrolling, competing with timeline REQs (console: `Large batch detected, limiting processing`).
+
+**Fix:**
+- Add a lightweight scroll-activity signal (`markScrolling()` from feed scroll handlers).
+- Lower `maxBatchSize` (64) and lengthen `batchScheduleFn` delay while scrolling (200ms vs 100ms idle).
+
+**Expected impact:** Profile fetches defer during scroll; timeline paint stays responsive.
+
+---
+
+## Fix 6 — Delete unused files and junk
+
+**Problem:** Knip reported 16 unused files plus `src/services/Untitled` (accidental single-character junk). No runtime cost, but bundle/clarity noise.
+
+**Files removed:**
+
+| Cluster | Files |
+|---------|--------|
+| Connected relays UI | `ActiveRelaysDropdownSection.tsx`, `ActiveRelaysIconGrid.tsx`, `active-relays-display.ts` |
+| Old Explore tabs | `Explore/index.tsx`, `ExploreFavoriteRelays.tsx`, `ExplorePopularRelays.tsx`, `ExploreRelayReviews.tsx` |
+| Other UI | `FollowingFavoriteRelayList`, `SeenOnButton`, `NotificationThreadWatchButtons`, `ProfileTimeline`, `Tabs/index.tsx`, `ProfileSearchBar`, `QuickZapSwitch` |
+| Hooks | `useBtcUsdRate.ts`, `useRelayConnectionRows.ts` |
+| Junk | `src/services/Untitled` |
+
+**Note:** `useProfileTimeline` hook and `ExploreRelayDirectory` remain in use; only dead wrappers were removed.
+
+---
+
+## Fix 7 — YouTube iframe API poll timeout
+
+**File:** `src/lib/youtube-iframe-api.ts`
+
+**Problem:** When the YouTube script tag was already present but `YT.Player` never became available, `requestAnimationFrame` polled forever.
+
+**Fix:** Cap polling (e.g. 5s / ~300 frames). Resolve the promise anyway so embeds fail gracefully instead of leaking rAF work.
+
+---
+
+## Verification
+
+After applying all fixes:
+
+```bash
+npm run test -- --run src/lib/profile-author-warmup-spec.test.ts src/components/PostEditor/PostTextarea/Mention/mention-range.test.ts
+npx tsc --noEmit
+```
+
+Manual checks:
+
+1. Home feed scroll — no jank spike when many authors are visible.
+2. @-mention search — still finds cached profiles after IDB cap.
+3. YouTube embeds — still load when API is healthy; no infinite rAF when blocked.
+
+---
+
+## Phase 2 — Archives API was additive, not a replacement (2026-06-07)
+
+**Why it still felt sluggish:** Nostr Archives REST was wired in parallel with relays for profiles/search, but **feed note stats still fired full relay REQ waves** for every visible card even when Archives already had interaction counts. Archives also consumed the shared **100 req/min** budget via sequential interaction prefetch, while relay work continued unchanged.
+
+### Fix A — Feed cards: Archives-only stats
+
+**File:** `src/components/NoteStats/index.tsx`
+
+Background feed cards (`!foregroundStats`) now call `prefetchArchivesInteractions` only. Relay `fetchNoteStats` runs on foreground surfaces (open note, thread, interactions panel).
+
+### Fix B — Parallel Archives interaction prefetch
+
+**File:** `src/lib/note-stats-archives-prefetch.ts`
+
+Prefetch runs with concurrency 5 instead of one note at a time.
+
+### Fix C — Archives-first profile batch
+
+**File:** `src/lib/profile-metadata-batch.ts`
+
+Await Archives metadata (400ms cap), then relay-fetch **only pubkeys Archives did not return** — avoids duplicate kind-0 storms.
+
+### Fix D — Remove 120× `subscribeNoteStats` in NoteList
+
+**File:** `src/components/NoteList/index.tsx`
+
+Dropped per-visible-note stats subscriptions that re-triggered profile batches on every Archives count update.
+
+### Fix E — Stabilize superchat filter
+
+**File:** `src/components/NoteList/index.tsx`
+
+`feedAttestedSuperchatIds` read from a ref inside `shouldHideEvent` so attestation updates do not rescan 2500 rows.
+
+### Fix F — Cap Archives blocking on thread resolve
+
+**File:** `src/lib/thread-context-local.ts`
+
+Archives event lookup races with a 700ms cap before falling through to local stores / relays.
+
+---
+
+## Related audit items (not in this pass)
+
+| Area | Notes |
+|------|--------|
+| `DeepBrowsingProvider` + `Tabs` | Scroll updates context → tab chrome re-renders |
+| `NostrProvider` | Account hydration causes broad tree updates |
+| `useFeedAttestedSuperchatIds` | New attestations invalidate `shouldHideEvent` → full feed re-scan |
+| `NoteList` stats subscriptions | Up to ~120 `subscribeNoteStats` listeners |
+| `RssFeedList` | 20s IndexedDB poll while mounted |
+| `client.service` | 45s HTTP timeline polling on index relays |
+| Knip unused exports | Mostly shadcn re-exports; low priority |
+
+The `while (true)` worker pool in `client.service.ts` (~line 390) is intentional and bounded.

src/components/Image/index.tsx

@@ -11,7 +11,7 @@ import {
 import { TImetaInfo } from '@/types'
 import { blurHashPlaceholderForMediaUrl } from '@/lib/media-placeholder-blurhash'
 import { decode } from 'blurhash'
-import { ImageOff } from 'lucide-react'
+import { Image as ImageIcon, ImageOff } from 'lucide-react'
 import {
   CSSProperties,
   HTMLAttributes,
@@ -332,16 +332,21 @@ export default function Image({
   }
 
   const hasHoverTip = Boolean(imgTitle)
+  const showTapToRevealChrome = !showErrorState && !revealed && effectiveHoldUntilClick
+  const tapToRevealLabel = t('Click to load image')
 
   return (
     <span className={cn('block w-full not-prose', classNames.wrapper)}>
       <span
         className={cn(
           'relative overflow-hidden block w-full rounded-lg bg-background',
+          showTapToRevealChrome && 'group cursor-zoom-in',
           hasHoverTip && 'cursor-help ring-1 ring-inset ring-dotted ring-muted-foreground/45'
         )}
         style={mergedWrapperStyle}
-        title={imgTitle}
+        title={showTapToRevealChrome ? tapToRevealLabel : imgTitle}
+        role={showTapToRevealChrome ? 'button' : undefined}
+        aria-label={showTapToRevealChrome ? tapToRevealLabel : undefined}
         onClick={handleWrapperClick}
         {...props}
       >
@@ -375,6 +380,19 @@ export default function Image({
           )}
         </span>
       )}
+      {showTapToRevealChrome && (
+        <>
+          <span
+            className="absolute inset-0 z-[15] bg-gradient-to-t from-black/55 via-black/25 to-black/15 pointer-events-none"
+            aria-hidden
+          />
+          <span className="absolute inset-0 z-[20] grid place-items-center pointer-events-none" aria-hidden>
+            <span className="flex size-14 items-center justify-center rounded-full bg-black/55 text-white shadow-md backdrop-blur-[2px] transition-transform group-hover:scale-105">
+              <ImageIcon className="size-7" strokeWidth={2} />
+            </span>
+          </span>
+        </>
+      )}
       {!showErrorState && revealed && (
         <img
           ref={imgRef}

src/components/NoteList/index.tsx

@@ -1072,6 +1072,10 @@ const NoteList = forwardRef(
     }, [subRequestsKey, feedSubscriptionKey])
 
     const feedAttestedSuperchatIds = useFeedAttestedSuperchatIds(feedRelayUrls)
+    const feedAttestedSuperchatIdsRef = useRef(feedAttestedSuperchatIds)
+    useEffect(() => {
+      feedAttestedSuperchatIdsRef.current = feedAttestedSuperchatIds
+    }, [feedAttestedSuperchatIds])
 
     const followingFeedDeltaSubRequestsKey = useMemo(
       () =>
@@ -1427,7 +1431,7 @@ const NoteList = forwardRef(
         if (
           !shouldIncludePaymentInFeed(
             evt,
-            feedAttestedSuperchatIds,
+            feedAttestedSuperchatIdsRef.current,
             incomingPaymentRecipientPubkey
           )
         ) {
@@ -1460,7 +1464,6 @@ const NoteList = forwardRef(
         mutePubkeySet,
         pinnedEventHexIdSet,
         isEventDeleted,
-        feedAttestedSuperchatIds,
         incomingPaymentRecipientPubkey,
         extraShouldHideEvent,
         homeFeedActiveSeenOnAllowlist,
@@ -1758,15 +1761,6 @@ const NoteList = forwardRef(
       clientFilteredVisibleCountRef.current = clientFilteredEvents.length
     }, [clientFilteredEvents.length])
 
-    const visibleNoteIdsForStatsPrefetchKey = useMemo(
-      () =>
-        clientFilteredEvents
-          .slice(0, Math.min(120, Math.max(showCount + 64, 64)))
-          .map((e) => e.id)
-          .join('\n'),
-      [clientFilteredEvents, showCount]
-    )
-
     const enqueueFeedProfilePubkeys = useCallback((need: string[]) => {
       if (need.length === 0) return
       const gen = feedProfileBatchGenRef.current
@@ -1830,51 +1824,6 @@ const NoteList = forwardRef(
       })()
     }, [])
 
-    const statsProfilePrefetchDebounceRef = useRef<ReturnType<typeof setTimeout> | null>(null)
-    const pendingStatsProfilePubkeysRef = useRef<Set<string>>(new Set())
-
-    useEffect(() => {
-      if (!visibleNoteIdsForStatsPrefetchKey) return
-      const ids = visibleNoteIdsForStatsPrefetchKey.split('\n').filter(Boolean)
-
-      const flushStatsProfiles = () => {
-        statsProfilePrefetchDebounceRef.current = null
-        const need = [...pendingStatsProfilePubkeysRef.current].filter(
-          (pk) => !feedProfileLoadedRef.current.has(pk)
-        )
-        pendingStatsProfilePubkeysRef.current.clear()
-        enqueueFeedProfilePubkeys(need)
-      }
-
-      const onStatsUpdate = (noteId: string) => {
-        const candidates = new Set<string>()
-        collectProfilePrefetchPubkeysFromNoteStats(noteStatsService.getNoteStats(noteId), candidates)
-        for (const pk of candidates) {
-          if (!feedProfileLoadedRef.current.has(pk)) {
-            pendingStatsProfilePubkeysRef.current.add(pk)
-          }
-        }
-        if (pendingStatsProfilePubkeysRef.current.size === 0) return
-        if (statsProfilePrefetchDebounceRef.current) {
-          clearTimeout(statsProfilePrefetchDebounceRef.current)
-        }
-        statsProfilePrefetchDebounceRef.current = setTimeout(
-          flushStatsProfiles,
-          FEED_PROFILE_BATCH_DEBOUNCE_MS
-        )
-      }
-
-      const unsubs = ids.map((id) => noteStatsService.subscribeNoteStats(id, () => onStatsUpdate(id)))
-      return () => {
-        unsubs.forEach((u) => u())
-        if (statsProfilePrefetchDebounceRef.current) {
-          clearTimeout(statsProfilePrefetchDebounceRef.current)
-          statsProfilePrefetchDebounceRef.current = null
-        }
-        pendingStatsProfilePubkeysRef.current.clear()
-      }
-    }, [visibleNoteIdsForStatsPrefetchKey, enqueueFeedProfilePubkeys])
-
     const clientFilteredNewEvents = useMemo(
       () =>
         showFeedClientFilter ? applyClientFeedFilter(filteredNewEvents) : filteredNewEvents,

src/components/NoteStats/index.tsx

@@ -116,6 +116,8 @@ export default function NoteStats({
     if (!fetchIfNotExisting) return
     if (shouldDeferStatsFetch && !isNearViewport) return
     noteStatsService.prefetchArchivesInteractions(event.id)
+    /** Feed cards: Archives aggregate counts are enough for badges — skip relay REQ storms. */
+    if (!foregroundStats) return
     setLoading(true)
     noteStatsService
       .fetchNoteStats(event, pubkey, statsRelaysRef.current, {

src/lib/note-stats-archives-prefetch.ts

@@ -4,6 +4,7 @@ import type { TArchivesInteractionCounts } from '@/types/nostr-archives'
 
 const BATCH_DELAY_MS = 48
 const MAX_BATCH_SIZE = 20
+const PREFETCH_CONCURRENCY = 5
 const RECENT_TTL_MS = 5 * 60_000
 
 const pending = new Set<string>()
@@ -53,8 +54,11 @@ async function flushBatch(): Promise<void> {
     pending.delete(id)
   }
 
-  for (const id of batch) {
-    if (!nostrArchivesApi.isAvailable()) break
+  let cursor = 0
+  const worker = async () => {
+    while (cursor < batch.length) {
+      if (!nostrArchivesApi.isAvailable()) return
+      const id = batch[cursor++]!
       inFlight.add(id)
       try {
         const res = await nostrArchivesApi.getEventInteractions(id)
@@ -66,6 +70,10 @@ async function flushBatch(): Promise<void> {
         inFlight.delete(id)
       }
     }
+  }
+  await Promise.all(
+    Array.from({ length: Math.min(PREFETCH_CONCURRENCY, batch.length) }, () => worker())
+  )
 
   if (pending.size > 0) scheduleBatch()
 }

src/lib/profile-metadata-batch.ts

@@ -53,14 +53,24 @@ export async function fetchProfilesMetadataBatch(pubkeys: readonly string[]): Pr
   try {
     const byPk = new Map<string, TProfile>()
 
-    const relayPromise = client.fetchProfilesForPubkeys(deduped).catch(() => [] as TProfile[])
     const archivesPromise = nostrArchivesApi.isAvailable()
       ? nostrArchivesApi.fetchProfilesMetadata(deduped)
       : Promise.resolve({ ok: false as const, reason: 'disabled' as const })
 
-    const [archivesRes, relayProfiles] = await Promise.all([archivesPromise, relayPromise])
+    const archivesRes = await Promise.race([
+      archivesPromise,
+      new Promise<{ ok: false; reason: 'timeout' }>((resolve) =>
+        setTimeout(() => resolve({ ok: false, reason: 'timeout' }), 400)
+      )
+    ])
     mergeArchivesProfiles(byPk, archivesRes)
 
+    const relayNeeded = deduped.filter((pk) => !byPk.has(pk))
+    const relayProfiles =
+      relayNeeded.length > 0
+        ? await client.fetchProfilesForPubkeys(relayNeeded).catch(() => [] as TProfile[])
+        : []
+
     for (const p of relayProfiles) {
       const pkNorm = p.pubkey.toLowerCase()
       if (!byPk.has(pkNorm)) {

src/lib/thread-context-local.ts

@@ -56,7 +56,10 @@ export async function resolveThreadContextEventFromLocalStores(
     return fromArchive
   }
 
-  const fromArchivesApi = await resolveNoteEventFromArchives(hex)
+  const fromArchivesApi = await Promise.race([
+    resolveNoteEventFromArchives(hex),
+    new Promise<undefined>((resolve) => setTimeout(resolve, 700))
+  ])
   if (fromArchivesApi && !shouldDropEventOnIngest(fromArchivesApi, { explicitNoteLookupHexId: hex })) {
     return fromArchivesApi
   }