HydraPaper is a wallpaper manager, specifically designed to work around the lack of functionality of many desktop environments to set a different wallpaper for each monitor in a multi monitor setup. It accomplishes this by scaling and merging different wallpapers into a single one and setting it as spanned.
It currently supports various desktop environments, including GNOME, MATE, Cinnamon and Budgie. Experimental support is included for the sway window manager.