This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.
language read-only property of the
TrackDefault interface returns a default language for an associated
SourceBuffer to use when an initialization segment does not contain language information for a new track.
This should be a valid language code, e.g.
var mylanguage = TrackDefault.language;
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