Definitive root cause of the black preview, proven in-browser: the live
.m3u8 was served Cache-Control: no-cache, so the browser cached the
playlist and served a STALE copy to hls.js's reloads (cache:'default'
stuck at one MEDIA-SEQUENCE while cache:'reload' advanced). hls.js saw the
live playlist as never advancing -> "live playlist MISSED" forever ->
never established the timeline -> never loaded a fragment -> readyState 0
(black), even though the stream itself is clean and advancing server-side.
Fix: serve live HLS (/live and /media/live) with
"no-store, no-cache, must-revalidate" + Pragma no-cache so the browser
never caches the playlist and every reload fetches the fresh live edge.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Zac Gaetano
24d10fda5d