--- /dev/null
+<?php
+
+namespace Drupal\Tests\layout_builder\FunctionalJavascript;
+
+use Drupal\FunctionalJavascriptTests\WebDriverTestBase;
+
+/**
+ * Field blocks tests for the override layout.
+ *
+ * @group layout_builder
+ */
+class ItemLayoutFieldBlockTest extends WebDriverTestBase {
+
+ /**
+ * {@inheritdoc}
+ */
+ protected static $modules = [
+ 'node',
+ 'layout_builder',
+ ];
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function setUp() {
+ parent::setUp();
+
+ $this->drupalLogin($this->drupalCreateUser([
+ 'configure any layout',
+ 'administer node display',
+ 'administer node fields',
+ ]));
+
+ // We need more then one content type for this test.
+ $this->createContentType(['type' => 'bundle_with_layout_overrides']);
+ $this->createContentType(['type' => 'filler_bundle']);
+ }
+
+ /**
+ * Tests configuring a field block for a user field.
+ */
+ public function testAddAjaxBlock() {
+ $assert_session = $this->assertSession();
+ $page = $this->getSession()->getPage();
+
+ // Allow overrides for the layout.
+ $this->drupalGet('admin/structure/types/manage/bundle_with_layout_overrides/display/default');
+ $page->checkField('layout[enabled]');
+ $page->checkField('layout[allow_custom]');
+ $page->pressButton('Save');
+
+ // Start by creating a node of type with layout overrides.
+ $node = $this->createNode([
+ 'type' => 'bundle_with_layout_overrides',
+ 'body' => [
+ [
+ 'value' => 'The node body',
+ ],
+ ],
+ ]);
+ $node->save();
+
+ // Open single item layout page.
+ $this->drupalGet('node/1/layout');
+
+ // Add a new block.
+ $this->clickLink('Add Block');
+ $assert_session->assertWaitOnAjaxRequest();
+
+ // Validate that only field blocks for layouted bundle are present.
+ $valid_links = $page->findAll('css', 'a[href$="field_block%3Anode%3Abundle_with_layout_overrides%3Abody"]');
+ $this->assertCount(1, $valid_links);
+ $invalid_links = $page->findAll('css', 'a[href$="field_block%3Anode%3Afiller_bundle%3Abody"]');
+ $this->assertCount(0, $invalid_links);
+ }
+
+}