Hi, i have solved with this code, putting into my functions.php
// Note that this intentionally disables a tinyMCE security feature.
// Use of this code is NOT recommended.
add_filter('tiny_mce_before_init','tinymce_allow_unsafe_link_target');
function tinymce_allow_unsafe_link_target( $mceInit ) {
$mceInit['allow_unsafe_link_target']=true;
return $mceInit;
}
very thanks