Custom Themes and chat background?

I've used a few texting app before and some of them has the ability to set custom background for chats, as in when you are dming someone or in a server texting, the background is always the default discord dark purple blue colour, so my idea is being able to customize that by putting pictures behind the texts or maybe even GIF.

and also for the custom theme is just simply being able to change the overall colour

Thank you discord if you want to use this idea, and keep up the work