diff --git a/core/modules/outside_in/tests/modules/offcanvas_test/src/Form/SidebarForm.php b/core/modules/outside_in/tests/modules/offcanvas_test/src/Form/OffcanvasForm.php
similarity index 90%
rename from core/modules/outside_in/tests/modules/offcanvas_test/src/Form/SidebarForm.php
rename to core/modules/outside_in/tests/modules/offcanvas_test/src/Form/OffcanvasForm.php
index 16c4f8d..0e6c526 100644
--- a/core/modules/outside_in/tests/modules/offcanvas_test/src/Form/SidebarForm.php
+++ b/core/modules/outside_in/tests/modules/offcanvas_test/src/Form/OffcanvasForm.php
@@ -9,7 +9,7 @@
 /**
  * @todo.
  */
-class SidebarForm implements PluginFormInterface, OperationAwareFormInterface {
+class OffcanvasForm implements PluginFormInterface, OperationAwareFormInterface {
 
   /**
    * @var string
diff --git a/core/modules/outside_in/tests/modules/offcanvas_test/src/Plugin/Block/TestBlock.php b/core/modules/outside_in/tests/modules/offcanvas_test/src/Plugin/Block/TestBlock.php
index 629a902..fcf7d5b 100644
--- a/core/modules/outside_in/tests/modules/offcanvas_test/src/Plugin/Block/TestBlock.php
+++ b/core/modules/outside_in/tests/modules/offcanvas_test/src/Plugin/Block/TestBlock.php
@@ -11,7 +11,7 @@
  * @Block(
  *   id = "offcanvas_links_block",
  *   form = {
- *     "sidebar" = "\Drupal\offcanvas_test\Form\SidebarForm"
+ *     "offcanvas" = "\Drupal\offcanvas_test\Form\OffcanvasForm"
  *   },
  *   admin_label = @Translation("Offcanvas test block")
  * )
diff --git a/core/modules/outside_in/tests/src/Kernel/MultipleBlockFormTest.php b/core/modules/outside_in/tests/src/Kernel/MultipleBlockFormTest.php
index 302a145..d0bef67 100644
--- a/core/modules/outside_in/tests/src/Kernel/MultipleBlockFormTest.php
+++ b/core/modules/outside_in/tests/src/Kernel/MultipleBlockFormTest.php
@@ -3,7 +3,7 @@
 namespace Drupal\Tests\outside_in\Kernel;
 
 use Drupal\KernelTests\KernelTestBase;
-use Drupal\offcanvas_test\Form\SidebarForm;
+use Drupal\offcanvas_test\Form\OffcanvasForm;
 
 /**
  * Tests that blocks can have multiple forms.
@@ -24,14 +24,14 @@ public function testMultipleForms() {
     $block = \Drupal::service('plugin.manager.block')->createInstance('offcanvas_links_block');
 
     $form_object1 = \Drupal::service('outside_in.block.manager')->getFormObject($block, 'default');
-    $form_object2 = \Drupal::service('outside_in.block.manager')->getFormObject($block, 'sidebar');
+    $form_object2 = \Drupal::service('outside_in.block.manager')->getFormObject($block, 'offcanvas');
 
     // Assert that the block itself is used for the default form.
     $this->assertSame($block, $form_object1);
 
-    $expected_sidebar = new SidebarForm();
-    $expected_sidebar->setOperation('sidebar');
-    $this->assertEquals($expected_sidebar, $form_object2);
+    $expected_offcanvas = new OffcanvasForm();
+    $expected_offcanvas->setOperation('offcanvas');
+    $this->assertEquals($expected_offcanvas, $form_object2);
   }
 
 }