I don't expect the Matroska specification to be adjusted for this to work soon, so in the meantime, follow the spec as written and add an option to support most files in the wild. I would prefer this to never be an option, but it looks like it's unavoidable. Recently, FFmpeg added cropping support for Matroska, so we don’t want to be the odd one out by doing it differently... See for more details: https://github.com/ietf-wg-cellar/matroska-specification/pull/947 https://gitlab.com/mbunkus/mkvtoolnix/-/issues/2389 https://github.com/mpv-player/mpv/pull/13446 Fixes: #15800