Restrict Usernames

By default, Joomla is quite permissive with its usernames, allowing virtually any character. However there are reasons why some sites may want to restrict usernames to specific formats or character sets. This plugin allows you to do this.

The plugin allows you to specify groups of characters that are permitted in usernames, and also a minimum/maximum length for them.

If the pre-defined options are insufficient, it also allows you to specify your own regular expression.