diff --git a/features/serializer/dynamic_groups.feature b/features/serializer/dynamic_groups.feature
new file mode 100644
index 00000000000..2454d0c2418
--- /dev/null
+++ b/features/serializer/dynamic_groups.feature
@@ -0,0 +1,11 @@
+@!mongodb
+Feature: Dynamic serialization context
+  In order to customize the Resource representation dynamically
+  As a developer
+  I should be able to add and remove groups 
+
+  @createSchema
+  Scenario: 
+    When I add "Content-Type" header equal to "application/ld+json"
+    And I send a "GET" request to "/relation_group_impact_on_collections/1"
+    And the JSON node "related.title" should be equal to "foo"
diff --git a/src/Serializer/AbstractItemNormalizer.php b/src/Serializer/AbstractItemNormalizer.php
index 3026aa66314..52c79f13c1f 100644
--- a/src/Serializer/AbstractItemNormalizer.php
+++ b/src/Serializer/AbstractItemNormalizer.php
@@ -507,18 +507,17 @@ protected function denormalizeRelation(string $attributeName, ApiProperty $prope
      */
     protected function getFactoryOptions(array $context): array
     {
-        $operationCacheKey = ($context['resource_class'] ?? '').($context['operation_name'] ?? '').($context['api_normalize'] ?? '');
-        if ($operationCacheKey && isset($this->localFactoryOptionsCache[$operationCacheKey])) {
-            return $this->localFactoryOptionsCache[$operationCacheKey];
-        }
-
         $options = [];
-
         if (isset($context[self::GROUPS])) {
             /* @see https://github.com/symfony/symfony/blob/v4.2.6/src/Symfony/Component/PropertyInfo/Extractor/SerializerExtractor.php */
             $options['serializer_groups'] = (array) $context[self::GROUPS];
         }
 
+        $operationCacheKey = ($context['resource_class'] ?? '').($context['operation_name'] ?? '').($context['api_normalize'] ?? '');
+        if ($operationCacheKey && isset($this->localFactoryOptionsCache[$operationCacheKey])) {
+            return $options + $this->localFactoryOptionsCache[$operationCacheKey];
+        }
+
         // This is a hot spot
         if (isset($context['resource_class'])) {
             // Note that the groups need to be read on the root operation
@@ -536,7 +535,7 @@ protected function getFactoryOptions(array $context): array
             }
         }
 
-        return $this->localFactoryOptionsCache[$operationCacheKey] = $options;
+        return $options + $this->localFactoryOptionsCache[$operationCacheKey] = $options;
     }
 
     /**
diff --git a/tests/Fixtures/TestBundle/Entity/RelationGroupImpactOnCollection.php b/tests/Fixtures/TestBundle/Entity/RelationGroupImpactOnCollection.php
index 8f74d613d4a..1a9a2e9b163 100644
--- a/tests/Fixtures/TestBundle/Entity/RelationGroupImpactOnCollection.php
+++ b/tests/Fixtures/TestBundle/Entity/RelationGroupImpactOnCollection.php
@@ -25,6 +25,8 @@
     operations: [
         new GetCollection(),
         new Get(normalizationContext: ['groups' => 'related']),
+        // This adds a "related" group in the "AddGroupNormalizer"
+        new Get(uriTemplate: '/custom_normalizer_relation_group_impact_on_collection'),
     ]
 )]
 class RelationGroupImpactOnCollection
diff --git a/tests/Fixtures/TestBundle/Serializer/Normalizer/AddGroupNormalizer.php b/tests/Fixtures/TestBundle/Serializer/Normalizer/AddGroupNormalizer.php
new file mode 100644
index 00000000000..e9439b7d03c
--- /dev/null
+++ b/tests/Fixtures/TestBundle/Serializer/Normalizer/AddGroupNormalizer.php
@@ -0,0 +1,51 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <dunglas@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Tests\Fixtures\TestBundle\Serializer\Normalizer;
+
+use ApiPlatform\Metadata\Get;
+use ApiPlatform\Tests\Fixtures\TestBundle\Entity\RelationGroupImpactOnCollection;
+use Symfony\Component\Serializer\Normalizer\NormalizerAwareInterface;
+use Symfony\Component\Serializer\Normalizer\NormalizerAwareTrait;
+use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
+
+final class AddGroupNormalizer implements NormalizerAwareInterface, NormalizerInterface
+{
+    use NormalizerAwareTrait;
+
+    private const ALREADY_CALLED = 'RELATED_GROUP_IMPACT_ON_COLLECTION_NORMALIZER_ALREADY_CALLED';
+
+    public function normalize($object, $format = null, array $context = []): array|string|int|float|bool|\ArrayObject
+    {
+        $context[self::ALREADY_CALLED] = true;
+        if (!($operation = $context['operation'] ?? null)) {
+            return $this->normalizer->normalize($object, $format, $context);
+        }
+
+        if ($operation instanceof Get && '/custom_normalizer_relation_group_impact_on_collection' === $operation->getUriTemplate()) {
+            $context['groups'] = ['related'];
+        }
+
+        return $this->normalizer->normalize($object, $format, $context);
+    }
+
+    public function supportsNormalization($data, $format = null, array $context = []): bool
+    {
+        // Make sure we're not called twice
+        if (isset($context[self::ALREADY_CALLED])) {
+            return false;
+        }
+
+        return $data instanceof RelationGroupImpactOnCollection;
+    }
+}
diff --git a/tests/Fixtures/app/config/config_common.yml b/tests/Fixtures/app/config/config_common.yml
index 96a0a3ae8a2..98ff470df5e 100644
--- a/tests/Fixtures/app/config/config_common.yml
+++ b/tests/Fixtures/app/config/config_common.yml
@@ -415,3 +415,7 @@ services:
         tags:
             - { name: 'api_platform.state_processor' }
 
+    ApiPlatform\Tests\Fixtures\TestBundle\Serializer\Normalizer\AddGroupNormalizer:
+        tags:
+            -  { name: 'serializer.normalizer' }
+