Preventing other GUI applications from stealing focus?

How can I prevent other applications from stealing focus from the active window? I have found solutions for other window managers, but nothing for "Metacity (Marco)" (the window manager of the MATE desktop manager). I don't want to have to specify every time which window must be "always on top", unless it can be done automatically every time I switch to a new window. I have determined the window manager by running wmctrl -m. EDIT: I have tried switching the focus-new-windows flag from smart to strict for both Gnome and Mate(Marco): $ gsettings set org.gnome.desktop.wm.preferences focus-new-windows strict $ gsettings set org.mate.Marco.general focus-new-windows strict But it didn't work.