wp-includes/SimplePie/src/HTTP/Psr7Response.php:77$namestring public function get_header(string $name): array { return $this->response->getHeader($name); }Unchanged from 6.9.7 through 7.1.0.
Signature, return type and hooks compared across 3 parsed releases.
src/wp-includes/SimplePie/src/HTTP/Psr7Response.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.