Remove gravatar from the WordPress Toolbar

plugin.php

<?php
/*
 * Entfernt das Gravatar aus der Toolbar.
 * @link: http://talkpress.de/artikel/wordpress-admin-bar-datenkrake-missbrauch
 */

/* < PHP 5.3 */
function ds_add_hide_avatar_filter() {
	add_filter( 'pre_option_show_avatars', '__return_zero' );
}
add_action( 'admin_bar_menu', 'ds_add_hide_avatar_filter', 0 );

function ds_remove_hide_avatar_filter() {
	remove_filter( 'pre_option_show_avatars', '__return_zero' );
}
add_action( 'admin_bar_menu', 'ds_remove_hide_avatar_filter', 10 ) ;


/* PHP 5.3 */
add_action(
	'admin_bar_menu',
	function() {
		add_filter( 'pre_option_show_avatars', '__return_zero' );
	},
	0
);

add_action(
	'admin_bar_menu',
	function() {
		remove_filter( 'pre_option_show_avatars', '__return_zero' );
	},
	10
);