diff --git a/core/modules/system/tests/modules/test_page_test/src/Controller/Test.php b/core/modules/system/tests/modules/test_page_test/src/Controller/Test.php
index e754eaf0c2..58797ce2fe 100644
--- a/core/modules/system/tests/modules/test_page_test/src/Controller/Test.php
+++ b/core/modules/system/tests/modules/test_page_test/src/Controller/Test.php
@@ -4,6 +4,7 @@
 
 use Drupal\Core\Url;
 use Symfony\Component\HttpFoundation\RedirectResponse;
+use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\HttpKernel\Exception\HttpException;
 
 /**
@@ -111,6 +112,17 @@ public function renderPipeInLink() {
     return ['#markup' => '<a href="http://example.com">foo|bar|baz</a>'];
   }
 
+  /**
+   * Renders all cookies from request.
+   *
+   * @return \Symfony\Component\HttpFoundation\Response
+   *   The response object.
+   */
+  public function renderRequestCookies() {
+    $cookies = \Drupal::request()->cookies->all();
+    return new Response(json_encode($cookies), 200);
+  }
+
   /**
    * Loads a page that does a redirect.
    *
diff --git a/core/modules/system/tests/modules/test_page_test/test_page_test.routing.yml b/core/modules/system/tests/modules/test_page_test/test_page_test.routing.yml
index e64a88d003..3dedee720a 100644
--- a/core/modules/system/tests/modules/test_page_test/test_page_test.routing.yml
+++ b/core/modules/system/tests/modules/test_page_test/test_page_test.routing.yml
@@ -90,3 +90,11 @@ test_page_test.meta_refresh:
     _controller: '\Drupal\test_page_test\Controller\Test::metaRefresh'
   requirements:
     _access: 'TRUE'
+
+test_page_test.request_cookies:
+  path: '/test-request-cookies'
+  defaults:
+    _title: 'Request Cookies'
+    _controller: '\Drupal\test_page_test\Controller\Test::renderRequestCookies'
+  requirements:
+    _access: 'TRUE'
diff --git a/core/tests/Drupal/FunctionalTests/BrowserTestBaseTest.php b/core/tests/Drupal/FunctionalTests/BrowserTestBaseTest.php
index 95ee39fd3a..968c60dedf 100644
--- a/core/tests/Drupal/FunctionalTests/BrowserTestBaseTest.php
+++ b/core/tests/Drupal/FunctionalTests/BrowserTestBaseTest.php
@@ -639,4 +639,41 @@ public function testGetDefaultDriveInstance() {
     $this->assertEquals([NULL, ['key1' => ['key2' => ['key3' => 3, 'key3.1' => 3.1]]]], $this->minkDefaultDriverArgs);
   }
 
+  /**
+   * Tests the ::getHttpClient() method with Xdebug mode.
+   *
+   * @dataProvider providerTestGetHttpClientXdebugOn
+   * @dataProvider providerTestGetHttpClientXdebugOff
+   */
+  public function testGetHttpClientWithXdebugMode($expected) {
+    $url = Url::fromRoute('test_page_test.request_cookies')->setAbsolute()->toString();
+    $response = $this->getHttpClient()->request('GET', $url);
+    $this->assertSame($expected, (string) $response->getBody());
+  }
+
+  /**
+   * Data provider for testGetHttpClientWithXdebugMode.
+   *
+   * @return array
+   *   Expected response.
+   */
+  public function providerTestGetHttpClientXdebugOn() {
+    putenv('XDEBUG_CONFIG=idekey=cake');
+    return [
+      'Xdebug On' => [json_encode(['XDEBUG_SESSION' => 'cake'])],
+    ];
+  }
+
+  /**
+   * Data provider for testGetHttpClientWithXdebugMode.
+   *
+   * @return array
+   *   Expected response.
+   */
+  public function providerTestGetHttpClientXdebugOff() {
+    return [
+      'Xdebug Off' => [''],
+    ];
+  }
+
 }
diff --git a/core/tests/Drupal/Tests/BrowserTestBase.php b/core/tests/Drupal/Tests/BrowserTestBase.php
index 4a983c05a1..2bef4fa092 100644
--- a/core/tests/Drupal/Tests/BrowserTestBase.php
+++ b/core/tests/Drupal/Tests/BrowserTestBase.php
@@ -23,6 +23,7 @@
 use Drupal\Tests\node\Traits\ContentTypeCreationTrait;
 use Drupal\Tests\node\Traits\NodeCreationTrait;
 use Drupal\Tests\user\Traits\UserCreationTrait;
+use GuzzleHttp\Cookie\CookieJar;
 use PHPUnit\Framework\TestCase;
 use Psr\Http\Message\RequestInterface;
 use Psr\Http\Message\ResponseInterface;
@@ -296,11 +297,24 @@ protected function initMink() {
     if ($driver instanceof GoutteDriver) {
       // Turn off curl timeout. Having a timeout is not a problem in a normal
       // test running, but it is a problem when debugging. Also, disable SSL
-      // peer verification so that testing under HTTPS always works.
+      // peer verification so that testing under HTTPS always works. Include
+      // cookies with XDEBUG_SESSION in the debugging.
+      $request = \Drupal::request();
+      $cookies_params = $this->extractCookiesFromRequest($request);
+      if (isset($cookies_params['XDEBUG_SESSION'])) {
+        $cookies = new CookieJar(TRUE, [
+          [
+            'Name' => 'XDEBUG_SESSION',
+            'Value' => current($cookies_params['XDEBUG_SESSION']),
+            'Domain' => $request->getHost(),
+          ],
+        ]);
+      }
       /** @var \GuzzleHttp\Client $client */
       $client = $this->container->get('http_client_factory')->fromOptions([
         'timeout' => NULL,
         'verify' => FALSE,
+        'cookies' => $cookies ?: FALSE,
       ]);
 
       // Inject a Guzzle middleware to generate debug output for every request