The For You feed awaited watchHistoryService.loadLatest() before rendering, and
loadLatest blocked on the full ~1500-item watch-history fetch on a cold load even
with allowStale:true (the `!allowStale || !hasCachedItems` guard awaited whenever
there was no cache). So the main feed froze behind the entire watch-history
resolution, and nothing re-ran the feed once history finished loading — watched
videos were never suppressed and watch-history tags never applied until a manual
refresh.
- watchHistoryService.loadLatest: allowStale callers now NEVER block. On a cold
load the refresh is kicked off in the background and the call returns
immediately with whatever is available (cached items, else the local queue).
- feedCoordinator.subscribeWatchHistoryFeedRefresh: subscribes to the
"fingerprint" event and, when the For You feed is active, debounced-re-runs it
so newly-resolved watched videos are suppressed and tags applied. Wired in at
bootstrap alongside feed registration.
The re-run reads the now-fresh cache (no further refresh scheduled), so there is
no loop. Adds feedCoordinatorWatchHistoryRefresh.test.mjs (debounced single
refresh while active; no refresh when inactive; idempotent subscription).
Co-Authored-By: Claude Opus 4.8 <[email protected]>
