Merge branch '6.0' into 6.1

* 6.0:
  Make FormErrorIterator generic
  [symfony/mailjet-mailer] Fix invalid mailjet error managment
  typehint of DkimOptions algorithm wrong
  Remove extra space in NotificationEmail
  Fix the usage of the Valid constraints in array-based forms
  Fix return value of `NullToken::getUser()`
  [DI] fix `ServiceSubscriberTrait` bug where parent has `__call()`
  [HttpClient] Fix reading proxy settings from dotenv when curl is used
  [Process] Don't return executable directories in PhpExecutableFinder
  Center icons vertically in trace list

Author: derrabus

CurlHttpClient.php

@@ -91,6 +91,10 @@ public function request(string $method, string $url, array $options = []): Respo
         $authority = $url['authority'];
         $host = parse_url($authority, \PHP_URL_HOST);
         $port = parse_url($authority, \PHP_URL_PORT) ?: ('http:' === $scheme ? 80 : 443);
+        $proxy = $options['proxy']
+            ?? ('https:' === $url['scheme'] ? $_SERVER['https_proxy'] ?? $_SERVER['HTTPS_PROXY'] ?? null : null)
+            // Ignore HTTP_PROXY except on the CLI to work around httpoxy set of vulnerabilities
+            ?? $_SERVER['http_proxy'] ?? (\in_array(\PHP_SAPI, ['cli', 'phpdbg'], true) ? $_SERVER['HTTP_PROXY'] ?? null : null) ?? $_SERVER['all_proxy'] ?? $_SERVER['ALL_PROXY'] ?? null;
         $url = implode('', $url);
 
         if (!isset($options['normalized_headers']['user-agent'])) {
@@ -106,7 +110,7 @@ public function request(string $method, string $url, array $options = []): Respo
             \CURLOPT_MAXREDIRS => 0 < $options['max_redirects'] ? $options['max_redirects'] : 0,
             \CURLOPT_COOKIEFILE => '', // Keep track of cookies during redirects
             \CURLOPT_TIMEOUT => 0,
-            \CURLOPT_PROXY => $options['proxy'],
+            \CURLOPT_PROXY => $proxy,
             \CURLOPT_NOPROXY => $options['no_proxy'] ?? $_SERVER['no_proxy'] ?? $_SERVER['NO_PROXY'] ?? '',
             \CURLOPT_SSL_VERIFYPEER => $options['verify_peer'],
             \CURLOPT_SSL_VERIFYHOST => $options['verify_host'] ? 2 : 0,
@@ -404,8 +408,15 @@ private static function createRedirectResolver(array $options, string $host, int
             }
 
             $url = self::parseUrl(curl_getinfo($ch, \CURLINFO_EFFECTIVE_URL));
+            $url = self::resolveUrl($location, $url);
 
-            return implode('', self::resolveUrl($location, $url));
+            curl_setopt($ch, \CURLOPT_PROXY, $options['proxy']
+                ?? ('https:' === $url['scheme'] ? $_SERVER['https_proxy'] ?? $_SERVER['HTTPS_PROXY'] ?? null : null)
+                // Ignore HTTP_PROXY except on the CLI to work around httpoxy set of vulnerabilities
+                ?? $_SERVER['http_proxy'] ?? (\in_array(\PHP_SAPI, ['cli', 'phpdbg'], true) ? $_SERVER['HTTP_PROXY'] ?? null : null) ?? $_SERVER['all_proxy'] ?? $_SERVER['ALL_PROXY'] ?? null
+            );
+
+            return implode('', $url);
         };
     }