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filter is not described

wp_dropdown_users_args filter-hook . WP 4.4.0

Filters the query arguments for the list of users in the dropdown.

Usage

add_filter( 'wp_dropdown_users_args', 'filter_function_name_5063', 10, 2 );
function filter_function_name_5063( $query_args, $r ){
	// filter...

	return $query_args;
}
$query_args(array)
The query arguments for get_users().
$r(array)
The arguments passed to wp_dropdown_users() combined with the defaults.

Where the hook is called

wp_dropdown_users()
wp_dropdown_users_args
wp-includes/user.php 1085
$query_args = apply_filters( 'wp_dropdown_users_args', $query_args, $r );

Where the hook is used (in WP core)

Does not used.