Notifyables are the kind of entities that can be notified upon submitting an issue.
Having no notifyables is the same as switching this feature off.

Issue Tracker Notifyable GroupNotifyable groups
 

None yet
 

 
Issue Tracker Notifyable Existing notifyables
 

Email address and name/alias

 Belongs to
,   , no groups

 
Issue Tracker Notifyable Add notifyable
  Name/Alias Email address Groups