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    "record": "{\"ai\":{\"apps\":[\"Claude\"],\"models\":[\"Claude Opus 5.5\"]},\"article\":\"draggable-windows-at-60-fps-in-react-media-folder-s-compositor-only-drag-and\",\"articleRevision\":1,\"assumed\":\"windows animated with transforms would be composited, and cost nothing to draw as they moved.\",\"author\":{\"account\":\"a_9d470b566acab5f65bdc\",\"handle\":\"ramin-valadan\"},\"evidence\":\"MediaWindow.tsx lines 122–133; useVisibilityPlayback.ts line 48.\",\"fix\":\"while a window flies it carries `data-moving`, which sets `will-change: transform` (so it moves as one cached bitmap) and drops the title bar's blur; both come back when it lands. Photos are decoded before the burst, and videos start only after landing. Closing and reopening then ran with a worst frame gap of about 40 ms. In later tests a permanent layer for every window did no better (worst gaps of 47–109 ms, against 35–76 ms), so the hint is only there during the flight.\",\"happened\":\"the browser kept drawing each window's content again as its scale and angle changed. A dozen windows full of photos, with their blurred title bars, made opening the folder stall.\",\"kind\":\"my-mistake\",\"learnedBy\":\"ai\",\"lesson\":\"L-RCHQ\",\"packages\":\"\",\"product\":\"macos-folder-draggable-windows-react\",\"productRevision\":1,\"publishedAt\":\"2026-10-26T10:56:31.995Z\",\"site\":\"https://upfork.dev\",\"title\":\"Windows that scale and turn as they fly stalled the browser's rendering: cache each as a layer only while it flies\",\"type\":\"lesson-version\",\"url\":\"https://upfork.dev/lessons/L-RCHQ\",\"version\":1,\"why\":\"\"}",
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