Ask iOS for the playback audio session on a page with a video

A TikTok post played perfectly and said nothing on an iPhone. The file was
not the problem: every rendition TikTok offers for it carries a full AAC
track, and the page as served measures loud audio in WebKit and Chromium
alike, straight through the /m/ proxy.

iOS is the problem. A video playing inline gets the "ambient" audio session,
which the Ring/Silent switch mutes; only going fullscreen gets the sound
back. Claiming "playback" says what is true of this page -- the sound is the
point, not decoration -- and the switch stops applying.

Declared only where there is a video, so an ordinary text post never claims
it, and the session activates when something plays rather than on load, so
it interrupts nothing on a page nobody presses play on.

Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01B3RUMiXa6eAW3okw9nB9NF

README.md

@@ -171,6 +171,10 @@ The one exception is Bluesky video, which is an HLS playlist — proxying it wou
 rewriting the manifest and every segment, so it is linked directly. Safari plays HLS
 natively; other browsers show a note.
 
+A page carrying a video asks iOS for the playback audio session. Without it a video
+playing inline is treated as ambience and the Ring/Silent switch mutes it, so the post
+plays perfectly and says nothing unless you go fullscreen.
+
 Resolved posts are cached in memory for an hour, so a reload or a back button doesn't
 drive the browser again.