diff --git a/core/modules/layout_builder/tests/src/Unit/LayoutBuilderRouteEnhancerTest.php b/core/modules/layout_builder/tests/src/Unit/LayoutBuilderRouteEnhancerTest.php
index 3736ce84e6..2904480d02 100644
--- a/core/modules/layout_builder/tests/src/Unit/LayoutBuilderRouteEnhancerTest.php
+++ b/core/modules/layout_builder/tests/src/Unit/LayoutBuilderRouteEnhancerTest.php
@@ -92,8 +92,12 @@ public function testEnhanceValidDefaults() {
       RouteObjectInterface::ROUTE_NAME => 'the_route_name',
       RouteObjectInterface::ROUTE_OBJECT => $route,
       'entity' => $object,
+      'is_rebuilding' => TRUE,
     ];
+    $result = $route_enhancer->enhance($defaults, new Request(['layout_is_rebuilding' => TRUE]));
+    $this->assertEquals($expected, $result);
 
+    $expected['is_rebuilding'] = FALSE;
     $result = $route_enhancer->enhance($defaults, new Request());
     $this->assertEquals($expected, $result);
     $this->assertSame($object, $result['entity']);