Gutenberg 9.2 was released this week and is the last release of the plugin to be rolled into WordPress 5.6. It features the long-awaited video tracks functionality, closing a ticket that has been open for more than two years under development.
Video tracks includes things like subtitles, captions, descriptions, chapters, and metadata. This update introduces a UI for adding video tags, which can contain multiple track elements using the following four attributes:
srclang (Valid BCP 47 language tag) label (Title for player UI) kind (Captions, Chapters, Descriptions, Metadata or Subtitles) src (URL of the text file)