File is the mp4 file from #2549 with the mdat atom zeroed out and compressed. We compress twice because apparently compressing 5MB of zeroes effectively in one run is too difficult for gzip. https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/2549 Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4560>