When a WP user creates a new Post the default behavior is that the Title is used as the basis for the Slug which forms a major part of the URL/Permalink. I am changing this default behavior.

My code (pasted below in case it helps) removes some common words, and reduces Slug length to about 6 words.

The problem is that the WP UI for the Post does not consistently update, and I need it to.

This is a typical chain of events:

1. Create new Post. URL/Permalink will be similar to: http://example.com/?p=32565
2. Enter a Title; The Small Dog Has Spoken Truth on Monday
3. Click “Save Draft”

Upon successful save, there are usually 1 of 2 outcomes.

• Either the URL now looks like the default WP one:
  http://example.com/the-small-dog-has-spoken-truth-on-monday/, or
• It remains as the one using the ID.

If I refresh (or leave and come back to the Post), the URL is http://example.com/small-dog-spoken-truth-monday/ – which is what I want it to be.

Is there another event, or method, be in in PHP or Javascript, where I can trigger WP to update the user interface so the Slug reflects the real (modified) one?

Outside of trial and error I am unsure how to proceed.

function slug_save_post_callback( $post_id, $post, $update ) {

    if (!empty($post->post_name)) { return; }
    if ($post->post_type != 'post' || $post->post_status == 'auto-draft') { return; }

    $slug = preg_replace("/[^A-Za-z0-9 ]/", '', $post->post_title);

    $remove_list = array(
        'a', 'an', 'and', 'are', 'as', 'at', 'be', 'but', 'by', 'can', 'cant', 'did', 'do',
        'for', 'from', 'get', 'got', 'had', 'has', 'hasnt', 'have', 'heres', 'how', 'i', 'in', 'is', 'its', 'just', 
        'k', 'like', 'not', 'o', 'of', 'off', 'on', 'only', 'or', 'ok', 'says', 'than', 'that', 'the', 'their', 'theyre', 'this', 'to', 'use',
        'what', 'whats', 'when', 'where', 'who', 'whom', 'why', 'will', 'with', 'wont', 'you'
    );

    foreach($remove_list as $word) {
        $slug = preg_replace("/\b$word\b/i", "", $slug);
    }

    $slug = explode("-", sanitize_title($slug));
    $slug = implode("-", array_slice($slug, 0, 6));
    if ($slug == $post->post_name) { return; }

    remove_action( 'save_post', 'slug_save_post_callback', 10, 3 );

    wp_update_post(array(
        'ID'        => $post_id,
        'post_name' => $slug
    ));

    add_action( 'save_post', 'slug_save_post_callback', 10, 3 );
}
add_action( 'save_post', 'slug_save_post_callback', 10, 3 );