JochenKnochen

…okay, i found a plugin which absolutely does waht i need:
https://wordpress.org/plugins/multiple-term-selection-widget/

Thanks alot for your quick and awesome support!!!!!! otherwise i would have spent hours and hours to find a solution on this “bug” 😉

…this is the test-page: http://jan.thorstenbreyer.de/

it’s just the standard twenty-13 theme and no plugins running!??!
thats weird.. it happens on different installations, different webproviders and with different themes!

thanks for oyur help,
Jochen

PS: i could prove a backend-login (how do i send private messages here?)

okay, sorry… i got it! i will look for another solution..
thanks anyway!

thanks!
but unfortunately this is not working for me… i copied the first codesnippet into my functions.php and putted the hidden input field somewhere in my site… then i added the last snippet to the first one like this:

add_action( 'save_post', 'update_linked_posts', 10, 2 );

function update_linked_posts( $post_ID, $post ) {

    // avoid recursion
    remove_filter( current_filter(), __FUNCTION__ );

    // get an array of post IDs from the other blogs, this is a custom function
    $linked_posts    = get_linked_post_ids( $post_ID );
    $current_blog_id = get_current_blog_id();

    foreach ( $linked_posts as $blog_id => $linked_post_id ) {

        switch_to_blog( $blog_id );

        $linked_post = get_post( $linked_post_id );

        // post doesn't exist anymore
        if ( ! $linked_post ) {
            // remove it from our table, this is a custom function
            delete_linked_post_relation( $linked_post_id );
        }
        else {
            // assuming you did proper security checks earlier!
            $linked_post->post_content = $_POST[ $blog_id ][ 'post_content' ];

            // YOUR METABOX BREAKS HERE
            wp_update_post( $linked_post );
        }

        restore_current_blog();
    }

    // restore the action callback
    add_action( 'save_post', 'update_linked_posts', 10, 2 );

// Network compatibility. Our plugin should not be synchronized.
        if ( empty ( $_POST[ 'blog_id' ] ) )
            return FALSE;

        if ( (int) $_POST[ 'blog_id' ] !== get_current_blog_id() )
            return FALSE;
}

…this must be simple… nobody?

i updated my htaccess like how the multisite installation process told me… or do i have to add something more? how do i add allowoverride to the httpd.conf? thanks so far…