[VIDEO FORMAT MP4, mandatory]:
Codec: avc1, H.264/MPEG-4 AVC
Resolution min: 1920 X 1080 px
Video has to loop just once in the file and will be repeated automatically.

[VIDEO FORMAT WEBM, mandatory]

[VIDEO PREVIEW IMAGE, mandatory] 16:9 image

Animation is only played on desktop devices.
On mobile devices the preview image is displayed.