Support MP4 video encoded in the AV1 standard format.
AV1 is a video encoding standard developed by Open Media Alliance consisting of Amazon, Apple, ARM, Cisco, Facebook, Google, IBM, Intel, Microsoft (!), Mozilla, Netflix, Nvidia, Samsung Electronics and Tencent and others, rivaling with VP9, H.264, H.265 and H.266 as a patent-free alternative. Major browsers support natively playing it already. I think it's time for OneDrive to understand videos (at least in MP4) when uploaded in this format, show previews for them, and allow online playback.