This plugin could also have been called Don't bother Site Administrator with every other Comment Moderation Notifications, unless the author has no moderation rights but since that's longer title, I chose to keep it as simple as I could.
But when that comment is held for moderation then the notification is sent to both the Author and Administrative moderator e-mail address as configured under Settings > General at the same time..
For many blogs or sites where the owner is the author and his account uses the same e-mail address as Administrative moderator e-mail address, this will boil down to one message to one address.
But when Site Admin is not the author, like on colaboration sites or sites managed by webmaster or designer where other people like the client posts, this might in flooding the mailbox with moderation messages that are not really his her concern.
If, by any chance, the author has no moderation rights or there is no author e-mail set then the default site e-mail address will still get the notification..
The plugin will do one thing make comment moderation notifications go to the authors e-mail address, and no longer the moderator address...
Check your Settings > Discussion settings and make sure that at E-mail me whenever at least comment is held for moderation and at Before comment appears at least Comment author must have previously approved comment are checked..
Open browser window, go to your site as visitor and post comment to post from anyone with at least author level other than the main site administrator..
Switch back to your browser window, verify that comment went into the queue, verify that you as site administrator did not receive any moderation e-mail and then ask the author if he she did receive the notification correctly
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