very useful while trying wallpapers, with pywal:

open terminals with the programs you normally use, that are influenced by pywal live (alacritty in my case)

Then run this in your wallpaper folder:

feh -Z -F --action1 ";feh --bg-scale %F; wal -i %F"

It'll get a slideshow from all images in the current folder, and whenever you press '1' it'll set that wallpaper, and run pywal with it as an argument. Then you can see how it looks with the windows you opened previously :3

[video coming soon in a reply]