Video background mobile fallback

Hi, I have a feature request this time 🙂
It makes absolutely sense not to diplay video backgrounds on small devices, however, a dull grey rectangle seems a pretty nasty fallback.
Since getting a video screenshot is as easy as this

https://img.youtube.com/vi/<video-id-here>/maxresdefault.jpg

it would be a simple and fancy solution use this as a background on small screens.

There is more about youtube thumbnails here https://stackoverflow.com/questions/2068344/how-do-i-get-a-youtube-video-thumbnail-from-the-youtube-api#2068371

I hope it won’t be much of a trouble to implement this.

Thanks in advance 🙂