diff --git a/core/modules/config/src/Tests/ConfigSchemaTest.php b/core/modules/config/src/Tests/ConfigSchemaTest.php
index fae3923..5dbec35 100644
--- a/core/modules/config/src/Tests/ConfigSchemaTest.php
+++ b/core/modules/config/src/Tests/ConfigSchemaTest.php
@@ -166,6 +166,9 @@ function testSchemaMapping() {
     $expected['mapping']['effects']['sequence'][0]['mapping']['data']['type'] = 'image.effect.[%parent.id]';
     $expected['mapping']['effects']['sequence'][0]['mapping']['weight']['type'] = 'integer';
     $expected['mapping']['effects']['sequence'][0]['mapping']['uuid']['type'] = 'string';
+    $expected['mapping']['third_party_settings']['type'] = 'sequence';
+    $expected['mapping']['third_party_settings']['label'] = 'Third party settings';
+    $expected['mapping']['third_party_settings']['sequence'][0]['type'] = 'image_style.third_party.[%key]';
     $expected['type'] = 'image.style.*';
 
     $this->assertEqual($definition, $expected);
diff --git a/core/modules/image/config/schema/image.schema.yml b/core/modules/image/config/schema/image.schema.yml
index 4f1fc79..88075cf 100644
--- a/core/modules/image/config/schema/image.schema.yml
+++ b/core/modules/image/config/schema/image.schema.yml
@@ -22,6 +22,11 @@ image.style.*:
               type: integer
             uuid:
               type: string
+    third_party_settings:
+      type: sequence
+      label: 'Third party settings'
+      sequence:
+        - type: image_style.third_party.[%key]
 
 image.effect.image_crop:
   type: image_size
diff --git a/core/modules/image/src/Entity/ImageStyle.php b/core/modules/image/src/Entity/ImageStyle.php
index 4506891..8d6e3dd 100644
--- a/core/modules/image/src/Entity/ImageStyle.php
+++ b/core/modules/image/src/Entity/ImageStyle.php
@@ -9,6 +9,8 @@
 
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Config\Entity\ConfigEntityBase;
+use Drupal\Core\Config\Entity\ThirdPartySettingsInterface;
+use Drupal\Core\Config\Entity\ThirdPartySettingsTrait;
 use Drupal\Core\Entity\EntityStorageInterface;
 use Drupal\Core\Entity\EntityWithPluginBagsInterface;
 use Drupal\Core\Routing\RequestHelper;
@@ -48,7 +50,9 @@
  *   }
  * )
  */
-class ImageStyle extends ConfigEntityBase implements ImageStyleInterface, EntityWithPluginBagsInterface {
+class ImageStyle extends ConfigEntityBase implements ImageStyleInterface, EntityWithPluginBagsInterface, ThirdPartySettingsInterface {
+
+  use ThirdPartySettingsTrait;
 
   /**
    * The name of the image style to use as replacement upon delete.
