Great question — answering as the UphillTech team:
object-fit seems to be working but the video doesn't take up all the vertical space of its parent element. If you can use height: 100vh on the video tag, it should work. On another note - for a background video like this, native HTML5 video does the job as well ...
Full answer by peperoli: https://stackoverflow.stackexchange.com/a/75445261 (CC BY-SA 4.0).
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