The web player clients need two things beyond the PO token: (1) a JavaScript runtime for
YouTube's 'n' signature challenge — install Deno (v2.9.1) + yt-dlp[default] (bundles yt-dlp-ejs
solver scripts); auto-detected on PATH. (2) an audio source — the web clients only expose
video-only DASH, so add the 'android' client (also PO-token-backed) for audio/muxed formats.
Player clients: web_safari,web,android (dropped tv — it falsely reports normal videos as DRM).
End-to-end verified in the worker: extraction (POT + Deno n-challenge) + download completes,
no bot/DRM/format errors. Full YouTube stack now: force-ipv4 + bgutil POT sidecar + Deno.