Anime releases often carry two subtitle tracks in one language, the
dialogue and a "Signs & Songs" track, and the second is as often as not
the one marked default or forced. mpv, picking by language, played it.
pstr_core::subtitles reads a track's name and forced flag for whether it
is the dialogue, and every client asks it once per file, after mpv has
made its own pick, whether to switch to a track in the same language
that is. A subtitle track the viewer chose by name stays, and subtitles
that are off stay off.
The phones have had this, and the desktop could only set languages from
the player, after a file had already opened in the wrong one. Settings
now has an audio language and a subtitle choice: off, the file's
default, or a language. The names come from the list pstr-player already
names tracks with, now exported as LANGUAGES.
A track picked on one episode now carries over to the next by its title as
well as its language, so e.g. "Signs & Songs" vs "Full" subtitles in the same
language stick. Catalog migration V8 adds the title columns; the Android
bridge keeps a stored title only while its language is unchanged.
nvrl