diff --git a/core/modules/outside_in/tests/src/FunctionalJavascript/OutsideInBlockFormTest.php b/core/modules/outside_in/tests/src/FunctionalJavascript/OutsideInBlockFormTest.php
index 0d0abc7..e9c4dfb 100644
--- a/core/modules/outside_in/tests/src/FunctionalJavascript/OutsideInBlockFormTest.php
+++ b/core/modules/outside_in/tests/src/FunctionalJavascript/OutsideInBlockFormTest.php
@@ -128,6 +128,8 @@ public function testBlocks($block_plugin, $new_page_text, $element_selector, $la
       $web_assert->elementTextContains('css', '#drupal-live-announce', 'Exited edit mode.');
       $web_assert->elementTextNotContains('css', '.contextual-toolbar-tab button', 'Editing');
       $web_assert->elementAttributeNotContains('css', '.dialog-offcanvas__main-canvas', 'class', 'js-outside-in-edit-mode');
+      // Delete the block that was placed for the current theme.
+      $block->delete();
     }
   }