Discourse_publish_format_html -> rewrite topic title?

Support WordPress
2

Try hooking into the wpdc_publish_format_title filter. It’s passed two arguments: $title and $post_id.

Something like this should work:

add_filter( 'wpdc_publish_format_title', 'wpdc_custom_publish_format_title', 10, 2 );
function wpdc_custom_publish_format_title( $title, $post_id ) {
    if ( get_post_meta( $post_id, 'your_meta_key', true ) ) {
        // Modify $title here.
    }

    return $title;
}