get_webfinger();
			return $metadata;
		}
		if ( \is_author() ) {
			// Use the Author of the Archive-Page
			$user_id = \get_queried_object_id();
		} elseif ( \is_singular() ) {
			// Use the Author of the Post
			$user_id = \get_post_field( 'post_author', \get_queried_object_id() );
		} elseif ( ! is_user_type_disabled( 'blog' ) ) {
			// Use the Blog-User for any other page, if the Blog-User is not disabled
			$user_id = Users::BLOG_USER_ID;
		} else {
			// Do not add any metadata otherwise
			return $metadata;
		}
		$user = Users::get_by_id( $user_id );
		if ( ! $user || \is_wp_error( $user ) ) {
			return $metadata;
		}
		// add WebFinger resource
		$metadata['fediverse:creator'] = $user->get_webfinger();
		return $metadata;
	}
	/**
	 * Output Open Graph  tags in the page header.
	 */
	public static function add_meta_tags() {
		$metadata = apply_filters( 'opengraph_metadata', array() );
		foreach ( $metadata as $key => $value ) {
			if ( empty( $key ) || empty( $value ) ) {
				continue;
			}
			$value = (array) $value;
			foreach ( $value as $v ) {
				printf(
					'' . PHP_EOL,
					esc_attr( $key ),
					esc_attr( $v )
				);
			}
		}
	}
}