Create a new job, choose to use email-ext, and do not enter anything for the
global list. Then for the "Success" emails enter a recepient list (locally only
for success notification) and choose the checkbox "send to recipients". Message
notification is never send.
There is bug in the code, that never checks if the global recepients list is
empty. Then it silently fails with an error message in the console log, but
don't even print the stacktrace of the exception