How to set background for a Steam profile? - Arqade

I noticed some of my friends can change their Steam background profile. I searched in "Edit Profile" tab to edit mine but I don't see how. Can someone explain how to do this ?

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Find game which a Steam profile background is from? - Arqade

How to create a full background for your Steam profile

Steam Community :: Guide :: How to Identify Profile Backgrounds

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How To Get A Background On Steam 2016 (EASY) - Steam Custom

Steam: Animated Borders, Backgrounds and Profiles Explained

SeeRjED's Steam Profile Designs on Behance

SeeRjED's Steam Profile Designs on Behance

Is it possible to set a cover art image for non steam game? - Arqade

How to Get, Customize & Change Your Steam Profile Background