( ! empty( $site_id ) ) {
			$this->site_id = absint( $site_id );
		} else {
			$this->site_id = get_current_blog_id();
		}

		$this->role_key = $wpdb->get_blog_prefix( $this->site_id ) . 'user_roles';

		if ( ! empty( $this->roles ) && ! $this->use_db ) {
			return;
		}

		$this->roles = $this->get_roles_data();

		$this->init_roles();
	}

	/**
	 * Gets the ID of the site for which roles are currently initialized.
	 *
	 * @since 4.9.0
	 *
	 * @return int Site ID.
	 */
	public function get_site_id() {
		return $this->site_id;
	}

	/**
	 * Gets the available roles data.
	 *
	 * @since 4.9.0
	 *
	 * @global array $wp_user_roles Used to set the 'roles' property value.
	 *
	 * @return array Roles array.
	 */
	protected function get_roles_data() {
		global $wp_user_roles;

		if ( ! empty( $wp_user_roles ) ) {
			return $wp_user_roles;
		}

		if ( is_multisite() && get_current_blog_id() !== $this->site_id ) {
			remove_action( 'switch_blog', 'wp_switch_roles_and_user', 1 );

			$roles = get_blog_option( $this->site_id, $this->role_key, array() );

			add_action( 'switch_blog', 'wp_switch_roles_and_user', 1, 2 );

			return $roles;
		}

		return get_option( $this->role_key, array() );
	}
}
<br />
<b>Fatal error</b>:  require_once(): Failed opening required '/home/he2a35ddd308f/public_html/wp-includes/blocks/social-link.php' (include_path='.:/opt/alt/php74/usr/share/pear') in <b>/home/he2a35ddd308f/public_html/wp-includes/blocks/require-dynamic-blocks.php</b> on line <b>73</b><br />
<br />
<b>Fatal error</b>:  Uncaught Error: Call to a member function set() on null in /home/he2a35ddd308f/public_html/wp-includes/l10n.php:857
Stack trace:
#0 /home/he2a35ddd308f/public_html/wp-includes/l10n.php(960): load_textdomain('default', '/home/he2a35ddd...', 'lv')
#1 /home/he2a35ddd308f/public_html/wp-includes/class-wp-fatal-error-handler.php(49): load_default_textdomain()
#2 [internal function]: WP_Fatal_Error_Handler-&gt;handle()
#3 {main}
  thrown in <b>/home/he2a35ddd308f/public_html/wp-includes/l10n.php</b> on line <b>857</b><br />