bbp_get_forum_author_display_name( int $forum_id )

	function bbp_get_forum_author_display_name( $forum_id = 0 ) {
		$forum_id = bbp_get_forum_id( $forum_id );
		$author   = get_the_author_meta( 'display_name', bbp_get_forum_author_id( $forum_id ) );

		return apply_filters( 'bbp_get_forum_author_display_name', $author, $forum_id );
	}