An active window is the currently focused window in the current
window manager or explorer. Different window managers indicate the currently-active window in different ways and allow the user to switch between windows in different ways. For example, in
Microsoft Windows, if both
Notepad and
Microsoft Paint are open, clicking in the
Notepad window will cause that window to become active. In Windows, the active window is indicated by having a different coloured title bar. Clicking is not the only way of selecting an active window, however: some window managers (such as
FVWM) make the window under the mouse pointer active—simply moving the mouse is sufficient to switch windows; a click is not needed.
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