Streams built for local folder files carry no resolution/codec/fps
metadata (unknowable before demux), so the quality selector labeled
them "Unknown". Use the video track mpv reports (demux-w/h/fps, codec)
to fill those fields into a display-only copy of the stream — the
Video row and summary now show e.g. "720p · 30fps" with a codec badge.
Selection and tap handling keep using the original stream.
Files with multiple embedded tracks (e.g. MKV from media sources or
downloads) previously exposed none of them: mpv's track-list was never
read, aid was never set, and sid was only ever no/auto. The quality
selector showed no Audio or Subtitles tab for such files.
MPVClient now observes track-list/aid/sid and delivers a coalesced,
leniently decoded [MPVTrack] snapshot; selection state is derived from
the reported "selected" flags. Embedded tracks are switched live via
aid/sid (no reload), surfaced in the existing Audio/Subtitles sections
alongside external captions on iOS, tvOS and macOS. External sub-add/
audio-add tracks are filtered out to avoid double-listing. User picks
are sticky across same-video reloads (quality switch, audio mode,
retries) and preferred audio/subtitle languages auto-select a matching
embedded track once per load, with external captions taking precedence.
