You have a couple of options for all emails that you can set in your config.php file.
If you want to stop all emails you can add (or set):
$cfg->sendemail = false;
If you want all emails sent to one particular email address - useful for diagnosing email problems:
$cfg->sendemail = true;
$cfg->sendallemailto = 'you@example.com';
Cheers
Robert
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