includes/class-freemius.php
function is_active_for_site( $blog_id ) {
            if ( ! is_multisite() ) {
                // Not a multisite and this code is executed, means that the plugin is active.
                return true;
            }

            if ( $this->is_theme() ) {
                // All themes are site level activated.
                return true;
            }

            if ( $this->_is_network_active ) {
                // Plugin was network activated so it's active.
                return true;
            }

            return in_array( $this->_plugin_basename, (array) get_blog_option( $blog_id, 'active_plugins', array() ) );
        }
function is_active_for_site( $blog_id ) {
            if ( ! is_multisite() ) {
                // Not a multisite and this code is executed, means that the plugin is active.
                return true;
            }

            if ( $this->is_theme() ) {
                // All themes are site level activated.
                return true;
            }

            if ( $this->_is_network_active ) {
                // Plugin was network activated so it's active.
                return true;
            }

            return in_array( $this->_plugin_basename, (array) get_blog_option( $blog_id, 'active_plugins', array() ) );
        }
function is_active_for_site ( $ blog_id ) { if ( ! is_multisite ( ) ) { // Not a multisite and this code is executed, means that the plugin is active.
 return true ; } if ( $ this -> is_theme ( ) ) { // All themes are site level activated.
 return true ; } if ( $ this -> _is_network_active ) { // Plugin was network activated so it's active.
 return true ; } return in_array ( $ this -> _plugin_basename , ( array ) get_blog_option ( $ blog_id , 'active_plugins' , array ( ) ) ) ; }
Check if the current module is active for the site.

@author Vova Feldman (@svovaf)
@since  2.0.0

@param int $blog_id

@return bool
Check if the current module is active for the site .