I have tried again WattOS 10 and the screenshot tool there by default it is Gnome Screenshot . I also noticed that scrot is also installed although it doesn't work. So there are 2 screenshot tools in WattOs 10.
GNOME Screenshot is a utility used in the GNOME desktop environment for taking screenshots. It was part of the GNOME Utilities (gnome-utils) package, but was split into its own package.
Gnome Screenshot is useless to me because of those pop ups it does everytime I try to take a screenshot. If I uninstall the Gnome Screenshot ... scrot doesn't take its place. The screenshot key on the keyboard just stops to work and a message pops up saying Gnome Screenshot isn't installed.