Watching a stream: a stream that's on plays through hls.js, held near the live edge (1.5 s back, up to 1.1× when it drifts past 5 s) — Chrome's own HLS player starts three segments back, never catches up, and fails outright (DEMUXER_ERROR_COULD_NOT_PARSE) if a page changes its speed. With the live server's 1 s segments a viewer is 3.5 s behind the broadcaster, from 8.6 s (go-live-test LATENCY=1 measures it: the broadcaster's camera is a clock in black and white blocks, read off the viewer's frame). Recordings, and streams where hls.js can't run (iOS), stay on the browser's player.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_013ZDf1cyCQLkfjftYhymZAg

1 files changed, 10 insertions, 2 deletions

diff --git a/src/features/messages.js b/src/features/messages.js
index 0b6d8f0..13e328a 100644
--- a/src/features/messages.js
+++ b/src/features/messages.js
@@ -8903,8 +8903,16 @@ export function messagesFeature(ctx) {
     el.addEventListener('hlsfatal', fail);
     el.addEventListener('playing', () => { if (w.err) { w.err = null; scheduleRepaint(); } });
     const go = () => el.play().catch(() => { el.muted = true; el.play().catch(() => {}); });
-    if (!isHls(src) || canHls()) { el.src = src; go(); return; }
-    import('../hls-player.js').then((m) => m.attachHls(el, src)).then((hls) => {
+    // A stream that's on plays through hls.js wherever it runs: it keeps the
+    // viewer near the live edge (starts 1.5 s back, speeds up when it falls
+    // behind). Chrome's own HLS player starts three segments back, never
+    // catches up, and fails outright if a page changes its speed. Its player
+    // still takes recordings, and live streams where hls.js can't run (iOS).
+    // Measured (go-live-test LATENCY=1, one machine): 2 s segments on
+    // Chrome's player 8.6 s behind the broadcaster; 1 s segments 4.5 s.
+    const live = src === liveStream(ev) && isHls(src) && typeof MediaSource !== 'undefined';
+    if (!isHls(src) || (canHls() && !live)) { el.src = src; go(); return; }
+    import('../hls-player.js').then((m) => m.attachHls(el, src, { live })).then((hls) => {
       if (w.video !== el) { try { hls && hls.destroy(); } catch {} return; }
       if (!hls) { w.err = 'noplayer'; scheduleRepaint(); return; }
       w.hls = hls; go();