Symfony version(s) affected

7.2.0

Description

Since deploying 7.2.0 in production today we are getting the occasional exception caught by Sentry (of a warning) when making http-client calls to remote sites.

Undefined array key "connection"

https://phil-taylor.sentry.io/share/issue/cf7fdf8815f3437f9faac44fd4d9065c/

The issue seems to have started with the PR #58562

dumping the headers dd($responses[$id]->headers); of a normal request, I can see there is no array key connection in the headers.

How to reproduce

<?php
// composer req symfony/http-client symfony/var-dumper

use Symfony\Component\HttpClient\CurlHttpClient;

error_reporting(E_ALL);
ini_set('display_errors',1);

require 'vendor/autoload.php';

$client = new CurlHttpClient();

$response = $client->request(
    'GET',
    'https://symfony.com/'
);

$content = $response->getContent(false);

// then edit CurlResponse.php and dd the headers before line 319

Possible Solution

check the array key exists before use

Additional Context

No response