diff --git a/core/modules/layout_builder/src/Plugin/SectionStorage/OverridesSectionStorage.php b/core/modules/layout_builder/src/Plugin/SectionStorage/OverridesSectionStorage.php
index 393941aac1c8684c27280039843018f854393134..1fefa2b455ea3a9ae9cd50066e320252868558c1 100644
--- a/core/modules/layout_builder/src/Plugin/SectionStorage/OverridesSectionStorage.php
+++ b/core/modules/layout_builder/src/Plugin/SectionStorage/OverridesSectionStorage.php
@@ -241,6 +241,7 @@ public function buildRoutes(RouteCollection $collection) {
// Ensure that upcasting is run in the correct order.
$options['parameters']['section_storage'] = [];
$options['parameters'][$entity_type_id]['type'] = 'entity:' . $entity_type_id;
+ $options['_admin_route'] = FALSE;
$template = $entity_type->getLinkTemplate('canonical') . '/layout';
$this->buildLayoutRoutes($collection, $this->getPluginDefinition(), $template, $defaults, $requirements, $options, $entity_type_id, $entity_type_id);
diff --git a/core/modules/layout_builder/tests/src/Functional/LayoutBuilderOverridesEditingThemeTest.php b/core/modules/layout_builder/tests/src/Functional/LayoutBuilderOverridesEditingThemeTest.php
new file mode 100644
index 0000000000000000000000000000000000000000..d89b3a7c0e099ca2dfba0ba70a0b4b3e2bb8400c
--- /dev/null
+++ b/core/modules/layout_builder/tests/src/Functional/LayoutBuilderOverridesEditingThemeTest.php
@@ -0,0 +1,122 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\Tests\layout_builder\Functional;
+
+use Drupal\block_content\Entity\BlockContent;
+use Drupal\block_content\Entity\BlockContentType;
+use Drupal\layout_builder\Entity\LayoutBuilderEntityViewDisplay;
+use Drupal\Tests\layout_builder\Traits\EnableLayoutBuilderTrait;
+use Drupal\user\Entity\Role;
+use Drupal\user\UserInterface;
+
+/**
+ * Tests overrides editing uses the correct theme.
+ *
+ * Block content is used for this test as its canonical & editing routes
+ * are in the admin section, so we need to test that layout builder editing
+ * uses the front end theme.
+ *
+ * @group layout_builder
+ */
+class LayoutBuilderOverridesEditingThemeTest extends LayoutBuilderTestBase {
+
+ use EnableLayoutBuilderTrait;
+
+ /**
+ * {@inheritdoc}
+ */
+ protected $defaultTheme = 'test_theme';
+
+ /**
+ * {@inheritdoc}
+ */
+ protected static $modules = [
+ 'block_content',
+ ];
+
+ /**
+ * Permissions to grant admin user.
+ */
+ protected array $permissions = [
+ 'administer blocks',
+ 'access block library',
+ 'administer block types',
+ 'administer block content',
+ 'administer block_content display',
+ 'configure any layout',
+ 'view the administration theme',
+ 'edit any basic block content',
+ ];
+
+ /**
+ * Admin user.
+ */
+ protected UserInterface $adminUser;
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function setUp(): void {
+ parent::setUp();
+ // Create a basic block content type.
+ BlockContentType::create([
+ 'id' => 'basic',
+ 'label' => 'Basic',
+ 'revision' => FALSE,
+ ])->save();
+ $this->adminUser = $this->drupalCreateUser($this->permissions);
+ }
+
+ /**
+ * Tests editing block content with Layout Builder.
+ */
+ public function testEditing(): void {
+ // Create a new role for additional permissions needed.
+ $role = Role::create([
+ 'id' => 'layout_builder_tester',
+ 'label' => 'Layout Builder Tester',
+ ]);
+ // Set a different theme for the admin pages. So we can assert the theme
+ // in Layout Builder is not the same as the admin theme.
+ \Drupal::service('theme_installer')->install(['claro']);
+ $this->config('system.theme')->set('admin', 'claro')->save();
+
+ // Enable layout builder for the block content display.
+ $display = LayoutBuilderEntityViewDisplay::create([
+ 'targetEntityType' => 'block_content',
+ 'bundle' => 'basic',
+ 'mode' => 'default',
+ 'status' => TRUE,
+ ]);
+ $display->save();
+ $this->enableLayoutBuilder($display);
+ $role->grantPermission('configure all basic block_content layout overrides');
+ $role->save();
+ $this->adminUser
+ ->addRole($role->id())
+ ->save();
+ $this->drupalLogin($this->adminUser);
+ // Create a block content and test the themes used.
+ $blockContent = BlockContent::create([
+ 'info' => $this->randomMachineName(),
+ 'type' => 'basic',
+ 'langcode' => 'en',
+ ]);
+ $blockContent->save();
+ // Assert the test_theme is being used for overrides.
+ $this->drupalGet('admin/content/block/' . $blockContent->id() . '/layout');
+ $this->assertSession()->statusCodeEquals(200);
+ // Assert the test_theme is being used.
+ $this->assertSession()->responseContains('test_theme/kitten.css');
+ // Assert the claro theme is not being used.
+ $this->assertSession()->elementNotExists('css', '#block-claro-content');
+ // Assert the default still uses the test_theme.
+ $this->drupalGet('admin/structure/block-content/manage/basic/display/default/layout');
+ $this->assertSession()->statusCodeEquals(200);
+ $this->assertSession()->responseContains('test_theme/kitten.css');
+ $this->assertSession()->elementNotExists('css', '#block-claro-content');
+ }
+
+}
diff --git a/core/modules/layout_builder/tests/src/Unit/OverridesSectionStorageTest.php b/core/modules/layout_builder/tests/src/Unit/OverridesSectionStorageTest.php
index a9f8ba3b4c2a705559b34aa9e3f2cdae1d697af9..fbafb7eef13b268b26f875535b043ca3def03071 100644
--- a/core/modules/layout_builder/tests/src/Unit/OverridesSectionStorageTest.php
+++ b/core/modules/layout_builder/tests/src/Unit/OverridesSectionStorageTest.php
@@ -272,6 +272,7 @@ public function testBuildRoutes() {
'from_canonical' => ['type' => 'entity:from_canonical'],
],
'_layout_builder' => TRUE,
+ '_admin_route' => FALSE,
]
),
'layout_builder.overrides.from_canonical.discard_changes' => new Route(
@@ -292,6 +293,7 @@ public function testBuildRoutes() {
'from_canonical' => ['type' => 'entity:from_canonical'],
],
'_layout_builder' => TRUE,
+ '_admin_route' => FALSE,
]
),
'layout_builder.overrides.from_canonical.revert' => new Route(
@@ -312,6 +314,7 @@ public function testBuildRoutes() {
'from_canonical' => ['type' => 'entity:from_canonical'],
],
'_layout_builder' => TRUE,
+ '_admin_route' => FALSE,
]
),
'layout_builder.overrides.with_string_id.view' => new Route(
@@ -332,6 +335,7 @@ public function testBuildRoutes() {
'with_string_id' => ['type' => 'entity:with_string_id'],
],
'_layout_builder' => TRUE,
+ '_admin_route' => FALSE,
]
),
'layout_builder.overrides.with_string_id.discard_changes' => new Route(
@@ -351,6 +355,7 @@ public function testBuildRoutes() {
'with_string_id' => ['type' => 'entity:with_string_id'],
],
'_layout_builder' => TRUE,
+ '_admin_route' => FALSE,
]
),
'layout_builder.overrides.with_string_id.revert' => new Route(
@@ -370,6 +375,7 @@ public function testBuildRoutes() {
'with_string_id' => ['type' => 'entity:with_string_id'],
],
'_layout_builder' => TRUE,
+ '_admin_route' => FALSE,
]
),
'layout_builder.overrides.with_integer_id.view' => new Route(
@@ -391,6 +397,7 @@ public function testBuildRoutes() {
'with_integer_id' => ['type' => 'entity:with_integer_id'],
],
'_layout_builder' => TRUE,
+ '_admin_route' => FALSE,
]
),
'layout_builder.overrides.with_integer_id.discard_changes' => new Route(
@@ -411,6 +418,7 @@ public function testBuildRoutes() {
'with_integer_id' => ['type' => 'entity:with_integer_id'],
],
'_layout_builder' => TRUE,
+ '_admin_route' => FALSE,
]
),
'layout_builder.overrides.with_integer_id.revert' => new Route(
@@ -431,6 +439,7 @@ public function testBuildRoutes() {
'with_integer_id' => ['type' => 'entity:with_integer_id'],
],
'_layout_builder' => TRUE,
+ '_admin_route' => FALSE,
]
),
];