private static function get_plugin_slug( $basename ) {
            if ( ! isset( self::$_plugins_info ) ) {
                self::$_plugins_info = get_site_transient( 'update_plugins' );
            }

            $slug = '';

            if ( is_object( self::$_plugins_info ) ) {
                if ( isset( self::$_plugins_info->no_update ) &&
                     isset( self::$_plugins_info->no_update[ $basename ] ) &&
                     ! empty( self::$_plugins_info->no_update[ $basename ]->slug )
                ) {
                    $slug = self::$_plugins_info->no_update[ $basename ]->slug;
                } else if ( isset( self::$_plugins_info->response ) &&
                            isset( self::$_plugins_info->response[ $basename ] ) &&
                            ! empty( self::$_plugins_info->response[ $basename ]->slug )
                ) {
                    $slug = self::$_plugins_info->response[ $basename ]->slug;
                }
            }

            if ( empty( $slug ) ) {
                // Try to find slug from FS data.
                $slug = self::find_slug_by_basename( $basename );
            }

            if ( empty( $slug ) ) {
                // Fallback to plugin's folder name.
                $slug = dirname( $basename );
            }

            return $slug;
        }