/**
 * Callback function for the 'separate_webmentions_from_comments' filter.
 *
 * @param mixed $option 
 * @return mixed The filtered value.
 */
function my_separate_webmentions_from_comments_callback( $option ) {
    // Your code here.
    return $option;
}
add_filter( 'separate_webmentions_from_comments', 'my_separate_webmentions_from_comments_callback' );

apply_filters( 'separate_webmentions_from_comments', get_option( 'webmention_separate_comment', 1 ) )