Toggles silence monitoring of windows. When silence is turned on and an affected window is switched into the background, you will receive the silence notification message in the status line after a specified period of inactivity (silence). The default timeout can be changed with the
silencewaitcommand or by specifying a number of seconds instead of
off. Silence is initially off for all windows.
Same as the
silencecommand except that the default setting for new windows is changed. Initial setting is `off'.