Ticket #18693: reset-pointer.php

<?php
/*
 * Plugin Name: Reset Pointer
 * Description: Reset a WordPress 3.3 pointer by appending ?reset-pointer=POINTER_ID to an admin URL.
 */

add_action( 'admin_init', 'reset_pointer' );

function reset_pointer() {
        if ( ! isset( $_REQUEST['reset-pointer'] ) )
                return;

        $meta = (string) get_user_meta( get_current_user_id(), 'dismissed_wp_pointers', true );
        $meta = str_replace( $_REQUEST['reset-pointer'], '', $meta );
        $meta = str_replace( ',,', ',', $meta );
        $meta = trim( $meta, ',' );

        update_user_meta( get_current_user_id(), 'dismissed_wp_pointers', $meta );
}