Support

No, there is no such feature in Admin Tools. Even if there was, you'd still get an email telling you that someone attempted to log in with one of the forbidden usernames. What you actually need to do is set the "Treat failed logins as security exceptions" to Yes and also set up the automatic IP ban. I would recommend setting it as: auto ban after 3 failed attempts in 1 minute, for 15 minutes. This is a nice balance between not auto-blocking users who forget their password –but insist on trying the wrong password– and blocking bots which try to log in to your site with inexistent / invalid credentials.

The login username feature is more complicated than you might imagine. Joomla! makes it easy to get a notification when a login is failed or successful. It is impossible to figure out what the username is unless you restrict such a feature to working ONLY with the core Joomla! login module and com_user. If you have a third party login module you would have to modify Admin Tools' code to make it work. This will never happen and will be consistently reported as a bug. Therefore I cannot implement something which I know will be broken and unfixable.

Regarding fine control of automatic blocking, this is also not a wise thing to do. Really! Let's forget the fact that it would be a 4 by 25 grid which is extremely tough for a human to understand and borderline torturous. It would also be excruciatingly slow to check. It would also be outright impossible to figure out WTF someone is / is not blocked. Please watch what you are wishing for. It's easy for me to implement this monstrous feature but it would be impossible to use or understand. Would you really want an impossible to understand black box to have the final say on who gets blocked from your site? Or would you end up filing dozens of support requests every month which would require me 30-60 minutes each to reply, resulting in me pulling out this monstrosity? There you have it.