diff --git a/core/lib/Drupal/Component/DependencyInjection/ContainerInterface.php b/core/lib/Drupal/Component/DependencyInjection/ContainerInterface.php
index 121a57dadc..9a74abbe00 100644
--- a/core/lib/Drupal/Component/DependencyInjection/ContainerInterface.php
+++ b/core/lib/Drupal/Component/DependencyInjection/ContainerInterface.php
@@ -5,7 +5,10 @@
 use Symfony\Component\DependencyInjection\ContainerInterface as BaseContainerInterface;
 
 /**
- * Documents the existing getServiceIds method.
+ * The interface for Drupal service container classes.
+ *
+ * This interface extends Symfony's ContainerInterface and adds methods for
+ * managing mappins of instantiated services to its IDs.
  */
 interface ContainerInterface extends BaseContainerInterface {
 
diff --git a/core/lib/Drupal/Component/DependencyInjection/Dumper/OptimizedPhpArrayDumper.php b/core/lib/Drupal/Component/DependencyInjection/Dumper/OptimizedPhpArrayDumper.php
index d567c394cc..69f7d35ad1 100644
--- a/core/lib/Drupal/Component/DependencyInjection/Dumper/OptimizedPhpArrayDumper.php
+++ b/core/lib/Drupal/Component/DependencyInjection/Dumper/OptimizedPhpArrayDumper.php
@@ -429,8 +429,8 @@ protected function dumpValue($value) {
     }
     elseif (is_object($value)) {
       // Drupal specific: Instantiated objects have a _serviceId parameter.
-      @trigger_error('_serviceId is deprecated in drupal:9.5.0 and is removed from drupal:10.0.0. Use DrupalKernelInterface::getServiceIdMapping() instead. See https://www.drupal.org/node/3292540', E_USER_DEPRECATED);
       if (isset($value->_serviceId)) {
+        @trigger_error('_serviceId is deprecated in drupal:9.5.0 and is removed from drupal:10.0.0. Use DrupalKernelInterface::getServiceIdMapping() instead. See https://www.drupal.org/node/3292540', E_USER_DEPRECATED);
         return $this->getReferenceCall($value->_serviceId);
       }
       throw new RuntimeException('Unable to dump a service container if a parameter is an object without _serviceId.');
diff --git a/core/lib/Drupal/Component/DependencyInjection/ServiceIdHashTrait.php b/core/lib/Drupal/Component/DependencyInjection/ServiceIdHashTrait.php
index dc92b298c9..d53f9cb650 100644
--- a/core/lib/Drupal/Component/DependencyInjection/ServiceIdHashTrait.php
+++ b/core/lib/Drupal/Component/DependencyInjection/ServiceIdHashTrait.php
@@ -15,7 +15,7 @@ trait ServiceIdHashTrait {
   public function getServiceIdMappings(): array {
     $mapping = [];
     foreach ($this->getServiceIds() as $service_id) {
-      if ($this->initialized($service_id) && $service_id != 'service_container') {
+      if ($this->initialized($service_id) && $service_id !== 'service_container') {
         $mapping[$this->generateServiceIdHash($this->get($service_id))] = $service_id;
       }
     }
diff --git a/core/lib/Drupal/Core/DependencyInjection/DependencySerializationTrait.php b/core/lib/Drupal/Core/DependencyInjection/DependencySerializationTrait.php
index 005d76ea54..a23a2f487a 100644
--- a/core/lib/Drupal/Core/DependencyInjection/DependencySerializationTrait.php
+++ b/core/lib/Drupal/Core/DependencyInjection/DependencySerializationTrait.php
@@ -38,7 +38,7 @@ public function __sleep() {
       foreach ($vars as $key => $value) {
         if ($value instanceof EntityStorageInterface) {
           // If a class member is an entity storage, only store the entity type
-          // ID the storage is for so it can be used to get a fresh object on
+          // ID the storage is for, so it can be used to get a fresh object on
           // unserialization. By doing this we prevent possible memory leaks
           // when the storage is serialized and it contains a static cache of
           // entity objects. Additionally we ensure that we'll not have multiple