wp-includes/class-wp-site.php:305$keystring$valuemixed public function __set( $key, $value ) { switch ( $key ) { case 'id': $this->blog_id = (string) $value; break; case 'network_id': $this->site_id = (string) $value; break; default: $this->$key = $value; } }Introduced in 4.6.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-site.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.