[orca-list] What's the function of orca+n in Evolution?

[Hermann <meinelisten onlinehome de>]

Hi,
the subject says it almost: In Evolution there's a key combination 
orca+n that toggles whether messages are displayed or not when a script 
is not active?
Which script, and what means "not active"? Toggling this does not change 
anything, or did I miss something?
Hermann

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