[FFmpeg-user] Metadata changes without copying

[John Ervin]

Is there a way to change metadata in place with ffmpeg?

Using the mkvtoolnix set of tools, one can modify metadata in place for
matroska containers as:

    $ mkvpropedit movie.mkv -s "title=My Movie"

It seems the same in ffmpeg requires a copy, why? Or am I missing something?

    $ ffmpeg movie.mkv -codec copy -metadata "title=My Movie" out.mkv