Howto change the darkmode wallpapers in Gnome

To change the darkmode wallpapers you need to make two same (png) wallpapers with different names. the first wallpaper nix-wallpaper-simple-dark-gray.png the second wallpaper bzjd66sdi85rwj7kd3zcdsi52xzhx69c-nix-wallpaper-simple-dark-gray.png Then go to your directory of the wallpapers in the terminal sudo unshare -m bash mount -o remount, rw /nix/store sudo cp nix-wallpaper-simple-dark-gray.png /nix/store/qhhkqmm0vjvf7dgghlp6xg1j6lcwmgn4-simple-dark-gray-2016-02-19/share/wallpapers/sim...