WordPress at a glance
filter is not described

validate_username filter-hook . WP 2.0.1

Filters whether the provided username is valid.

Usage

add_filter( 'validate_username', 'filter_function_name_3650', 10, 2 );
function filter_function_name_3650( $valid, $username ){
	// filter...

	return $valid;
}
$valid(true/false)
Whether given username is valid.
$username(string)
Username to check.

Changelog

Since 2.0.1 Introduced.

Where the hook is called

validate_username()
validate_username
wp-includes/user.php 1674
return apply_filters( 'validate_username', $valid, $username );

Where in WP core the hook is used WordPress

Usage not found.