A
FocusPolicy, available in most X/Unix environments, which acts like
FocusFollowsMouse except that if the mouse pointer goes over the background (the
RootWindow, in X parlance) the application/window which most recently had
KeyboardFocus loses focus. Compare with strict
FocusFollowsMouse, which then assigns focus to the
RootWindow. In most configurations, the
RootWindow only responds to a fixed set of key combinations which applications generally don't handle (instead they are passed up the window stack); thus there is usually no reason to specifically assign focus to the root window.
SloppyFocus generally only applies to keyboard events; if the pointer is in the root window and a
ContextSensitiveMenu is invoked, the default CSM is brought up and not the application which last had focus.
See also
ClickToFocus PointToFocus
CategoryUserInterface