diff --git a/core/assets/scaffold/files/default.services.yml b/core/assets/scaffold/files/default.services.yml
index 239ec7b3a560a03de2d7d8fb8cbf44ef5ca5b7da..dacb3f7e9e3e3ad0fe80ce7697cdb1e8bbf9deec 100644
--- a/core/assets/scaffold/files/default.services.yml
+++ b/core/assets/scaffold/files/default.services.yml
@@ -64,6 +64,11 @@ parameters:
     # \Drupal\Core\Session\SessionConfiguration::__construct()
     # @default 6
     sid_bits_per_character: 6
+    # By default, Drupal generates a session cookie name based on the full
+    # domain name. Set the name_suffix to a short random string to ensure this
+    # session cookie name is unique on different installations on the same
+    # domain and path (for example, when migrating from Drupal 7).
+    name_suffix: ''
   twig.config:
     # Twig debugging:
     #
diff --git a/core/core.services.yml b/core/core.services.yml
index 106db6a337a1aa10f983b787548761969b601784..0fe15302ae6eda0f82166dc98b13cc8c64057641 100644
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -17,6 +17,7 @@ parameters:
     cookie_samesite: Lax
     sid_length: 48
     sid_bits_per_character: 6
+    name_suffix: ''
   twig.config:
     debug: false
     auto_reload: null
diff --git a/core/lib/Drupal/Core/Session/SessionConfiguration.php b/core/lib/Drupal/Core/Session/SessionConfiguration.php
index d1e5de1d934e40f9760c84d16def656cccab1d79..541b94ab4c9678282299903ce86449e13a6c5702 100644
--- a/core/lib/Drupal/Core/Session/SessionConfiguration.php
+++ b/core/lib/Drupal/Core/Session/SessionConfiguration.php
@@ -25,9 +25,14 @@ class SessionConfiguration implements SessionConfigurationInterface {
    * @see https://www.php.net/manual/session.security.ini.php
    */
   public function __construct($options = []) {
-    // Provide sensible defaults for sid_length and sid_bits_per_character.
-    // See core/assets/scaffold/files/default.services.yml for more information.
-    $this->options = $options + ['sid_length' => 48, 'sid_bits_per_character' => 6];
+    // Provide sensible defaults for sid_length, sid_bits_per_character and
+    // name_suffix.
+    // @see core/assets/scaffold/files/default.services.yml
+    $this->options = $options + [
+      'sid_length' => 48,
+      'sid_bits_per_character' => 6,
+      'name_suffix' => '',
+    ];
   }
 
   /**
@@ -96,7 +101,7 @@ protected function getUnprefixedName(Request $request) {
     else {
       // Otherwise use $base_url as session name, without the protocol
       // to use the same session identifiers across HTTP and HTTPS.
-      $session_name = $request->getHost() . $request->getBasePath();
+      $session_name = $request->getHost() . $request->getBasePath() . $this->options['name_suffix'];
       // Replace "core" out of session_name so core scripts redirect properly,
       // specifically install.php.
       $session_name = preg_replace('#/core$#', '', $session_name);
diff --git a/core/tests/Drupal/Tests/Core/Session/SessionConfigurationTest.php b/core/tests/Drupal/Tests/Core/Session/SessionConfigurationTest.php
index 2a2cbeee18ba594649706454e55c3f2965919258..fd85368f4c4457a43702e13da7e9599635e44b20 100644
--- a/core/tests/Drupal/Tests/Core/Session/SessionConfigurationTest.php
+++ b/core/tests/Drupal/Tests/Core/Session/SessionConfigurationTest.php
@@ -266,11 +266,12 @@ public static function providerTestEnforcedSessionName() {
    *
    * @dataProvider providerTestConstructorDefaultSettings
    */
-  public function testConstructorDefaultSettings(array $options, int $expected_sid_length, int $expected_sid_bits_per_character) {
+  public function testConstructorDefaultSettings(array $options, int $expected_sid_length, int $expected_sid_bits_per_character, string $expected_name_suffix) {
     $config = $this->createSessionConfiguration($options);
     $options = $config->getOptions(Request::createFromGlobals());
     $this->assertSame($expected_sid_length, $options['sid_length']);
     $this->assertSame($expected_sid_bits_per_character, $options['sid_bits_per_character']);
+    $this->assertSame($expected_name_suffix, $options['name_suffix']);
   }
 
   /**
@@ -281,10 +282,11 @@ public function testConstructorDefaultSettings(array $options, int $expected_sid
    */
   public static function providerTestConstructorDefaultSettings() {
     return [
-      [[], 48, 6],
-      [['sid_length' => 100], 100, 6],
-      [['sid_bits_per_character' => 5], 48, 5],
-      [['sid_length' => 100, 'sid_bits_per_character' => 5], 100, 5],
+      [[], 48, 6, ''],
+      [['sid_length' => 100], 100, 6, ''],
+      [['sid_bits_per_character' => 5], 48, 5, ''],
+      [['name_suffix' => 'some-suffix'], 48, 6, 'some-suffix'],
+      [['sid_length' => 100, 'sid_bits_per_character' => 5, 'name_suffix' => 'some-suffix'], 100, 5, 'some-suffix'],
     ];
   }
 
diff --git a/sites/default/default.services.yml b/sites/default/default.services.yml
index 239ec7b3a560a03de2d7d8fb8cbf44ef5ca5b7da..dacb3f7e9e3e3ad0fe80ce7697cdb1e8bbf9deec 100644
--- a/sites/default/default.services.yml
+++ b/sites/default/default.services.yml
@@ -64,6 +64,11 @@ parameters:
     # \Drupal\Core\Session\SessionConfiguration::__construct()
     # @default 6
     sid_bits_per_character: 6
+    # By default, Drupal generates a session cookie name based on the full
+    # domain name. Set the name_suffix to a short random string to ensure this
+    # session cookie name is unique on different installations on the same
+    # domain and path (for example, when migrating from Drupal 7).
+    name_suffix: ''
   twig.config:
     # Twig debugging:
     #