Custom last_poster_block bbPress

    /** Last poster / freshness block for forums */
    public function custom_last_poster_block( $subforum_id = "" ) {
        echo BBP_Default::custom_get_last_poster_block( $subforum_id = "" );
    }

        public function custom_get_last_poster_block( $subforum_id = "" ) {

            if ( !empty( $subforum_id ) ) {
                // Main forum display with sub forums
                $output = "<div class='last-posted-topic-title'>";
                $output .= "<a href='". bbp_get_forum_last_topic_permalink( $subforum_id ) ."'>" . bbp_get_topic_last_reply_title( bbp_get_forum_last_active_id( $subforum_id ) ) . "</a>";
                $output .= "</div>";
                $output .= "<div class='last-posted-topic-user'>by ";
                    $author_id = bbp_get_forum_last_reply_author_id( $subforum_id );
                $output .= "<span class=\"bbp-author-avatar\">" . get_avatar( $author_id, '14' ) . "&nbsp;</span>";
                $output .= bbp_get_user_profile_link( $author_id );
                $output .= "</div>";
                $output .= "<div class='last-posted-topic-time'>";
                $output .= bbp_get_forum_last_active_time( $subforum_id );
                $output .= "</div>";
            } else {
                // forum category display (no sub forums list)
                $output = "<div class='last-posted-topic-title'>";
                $output .= "<a href='". bbp_get_forum_last_topic_permalink() ."'>" . bbp_get_topic_last_reply_title( bbp_get_forum_last_active_id() ) . "</a>";
                $output .= "</div>";
                $output .= "<div class='last-posted-topic-user'>by ";
                $output .= "<span class=\"bbp-author-avatar\">" . get_avatar( bbp_get_forum_last_reply_author_id(), '14' ) . "&nbsp;</span>";
                $output .= bbp_get_user_profile_link( bbp_get_forum_last_reply_author_id() );
                $output .= "</div>";
                $output .= "<div class='last-posted-topic-time'>";
                $output .= bbp_get_forum_last_active_time();
                $output .= "</div>";
            }

            return $output;

        }