112,118 bytes of <style> rode on every response — 40% of a 309,584-byte timeline page, byte-identical each time and uncacheable because it had no URL, while the JS assets already carried Cache-Control. Now one hashed asset served immutable: a rule change mints a new URL, so a stale cache is impossible without anyone revalidating. check-in: eb4793ee8e user: quarry tags: trunk