As specified in https://www.webmproject.org/vp9/mp4/ Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3260>
As specified in https://www.webmproject.org/vp9/mp4/ Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3260>