diff --git a/core/modules/layout_builder/js/layout-builder.es6.js b/core/modules/layout_builder/js/layout-builder.es6.js
index e19d93400b..6c5165fef0 100644
--- a/core/modules/layout_builder/js/layout-builder.es6.js
+++ b/core/modules/layout_builder/js/layout-builder.es6.js
@@ -1,6 +1,10 @@
 (($, { ajax, behaviors }) => {
   behaviors.layoutBuilder = {
     attach(context) {
+      $('[data-layout-block-uuid]').children().on('click mousedown', (e) => {
+        e.preventDefault();
+        e.stopPropagation();
+      });
       $(context).find('.layout-builder--layout__region').sortable({
         items: '> .draggable',
         connectWith: '.layout-builder--layout__region',
diff --git a/core/modules/layout_builder/js/layout-builder.js b/core/modules/layout_builder/js/layout-builder.js
index 0f0de275ef..9850b37a8d 100644
--- a/core/modules/layout_builder/js/layout-builder.js
+++ b/core/modules/layout_builder/js/layout-builder.js
@@ -11,6 +11,10 @@
 
   behaviors.layoutBuilder = {
     attach: function attach(context) {
+      $('[data-layout-block-uuid]').children().on('click mousedown', function (e) {
+        e.preventDefault();
+        e.stopPropagation();
+      });
       $(context).find('.layout-builder--layout__region').sortable({
         items: '> .draggable',
         connectWith: '.layout-builder--layout__region',
diff --git a/core/modules/layout_builder/tests/src/FunctionalJavascript/LayoutBuilderTest.php b/core/modules/layout_builder/tests/src/FunctionalJavascript/LayoutBuilderTest.php
new file mode 100644
index 0000000000..dc4e6887c5
--- /dev/null
+++ b/core/modules/layout_builder/tests/src/FunctionalJavascript/LayoutBuilderTest.php
@@ -0,0 +1,163 @@
+<?php
+
+namespace Drupal\Tests\layout_builder\FunctionalJavascript;
+
+use Drupal\block_content\Entity\BlockContent;
+use Drupal\block_content\Entity\BlockContentType;
+use Drupal\FunctionalJavascriptTests\JavascriptTestBase;
+
+/**
+ * Tests the Layout Builder UI Javascript functionality.
+ *
+ * @group layout_builder
+ */
+class LayoutBuilderTest extends JavascriptTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = [
+    'layout_builder',
+    'block',
+    'node',
+    'search',
+    'filter',
+    'filter_test',
+    'block_content',
+  ];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    // @todo The Layout Builder UI relies on local tasks; fix in
+    //   https://www.drupal.org/project/drupal/issues/2917777.
+    $this->drupalPlaceBlock('local_tasks_block');
+
+    $this->createContentType(['type' => 'bundle_with_section_field']);
+    $this->createNode([
+      'type' => 'bundle_with_section_field',
+      'title' => 'The first node title',
+      'body' => [
+        [
+          'value' => 'Node body',
+        ],
+      ],
+    ]);
+
+    $bundle = BlockContentType::create([
+      'id' => 'basic',
+      'label' => 'Basic block',
+      'revision' => 1,
+    ]);
+    $bundle->save();
+    block_content_add_body_field($bundle->id());
+
+    BlockContent::create([
+      'type' => 'basic',
+      'info' => 'Block with link',
+      'body' => [
+        // Create a link that should be disabled in the Layout Builder.
+        'value' => '<a href="/search/node">Take me away</a>',
+        'format' => 'full_html',
+      ],
+    ])->save();
+  }
+
+  /**
+   * Tests that forms and links are disabled in the Layout Builder preview.
+   *
+   * @throws \Behat\Mink\Exception\ElementNotFoundException
+   * @throws \Behat\Mink\Exception\ExpectationException
+   */
+  public function testFormsLinksDisabled() {
+    $assert_session = $this->assertSession();
+
+    $this->drupalLogin($this->drupalCreateUser([
+      'configure any layout',
+      'administer node display',
+      'administer node fields',
+      'search content',
+    ]));
+
+    $field_ui_prefix = 'admin/structure/types/manage/bundle_with_section_field';
+
+    $this->drupalGet("$field_ui_prefix/display-layout/default");
+
+    // Add a block with a link and one with a form.
+    $this->addBlock('Block with link', '.block-field-blockblock-contentbasicbody');
+    $this->addBlock('Search form', '.search-block-form');
+
+    // Ensure the links and forms are disable using the defaults.
+    $this->assertLinksFormDisabled();
+
+    $this->clickLink('Save Layout');
+    $assert_session->addressEquals("$field_ui_prefix/display/default");
+
+    // Enable overrides.
+    $this->drupalPostForm("$field_ui_prefix/display/default", ['layout[allow_custom]' => TRUE], 'Save');
+    $this->drupalGet('node/1/layout');
+
+    // Wait for search form to be rendered in the Layout Builder.
+    $this->assertNotEmpty($assert_session->waitForElement('css', '.search-block-form'));
+    // Ensure the links and forms are also disabled in using the override.
+    $this->assertLinksFormDisabled();
+  }
+
+  /**
+   * Adds a block in the Layout Builder.
+   *
+   * @param string $block_link_text
+   *   The link text to add the block.
+   * @param string $rendered_locator
+   *   The CSS locator to confirm the block was rendered.
+   *
+   * @throws \Behat\Mink\Exception\ElementNotFoundException
+   * @throws \Behat\Mink\Exception\ExpectationException
+   */
+  protected function addBlock($block_link_text, $rendered_locator) {
+    $assert_session = $this->assertSession();
+    $page = $this->getSession()->getPage();
+    // Add a new block.
+    $assert_session->linkExists('Add Block');
+    $this->clickLink('Add Block');
+
+    $this->assertNotEmpty($assert_session->waitForElementVisible('css', '#drupal-off-canvas'));
+    $assert_session->assertWaitOnAjaxRequest();
+
+    $assert_session->linkExists($block_link_text);
+    $this->clickLink($block_link_text);
+    // Wait for off-canvas dialog to reopen with block form.
+    $this->assertNotEmpty($assert_session->waitForElementVisible('css', ".layout-builder-add-block"));
+    $assert_session->assertWaitOnAjaxRequest();
+    $page->pressButton('Add Block');
+
+    // Wait for block form to be rendered in the Layout Builder.
+    $this->assertNotEmpty($assert_session->waitForElement('css', $rendered_locator));
+  }
+
+  /**
+   * Asserts that forms and links added inside the Layout Builder are disabled.
+   *
+   * @throws \Behat\Mink\Exception\ElementNotFoundException
+   * @throws \Behat\Mink\Exception\ExpectationException
+   */
+  protected function assertLinksFormDisabled() {
+    $address = $this->getUrl();
+    $assert_session = $this->assertSession();
+    $page = $this->getSession()->getPage();
+    $page->pressButton('Search');
+    // Ensure we didn't get redirected to the search page.
+    $this->assertEmpty($assert_session->waitForElement('css', '.search-form'));
+    $assert_session->addressEquals($address);
+
+    $assert_session->linkExists('Take me away');
+    $page->clickLink('Take me away');
+    // Ensure we didn't get redirected to the search page.
+    $this->assertEmpty($assert_session->waitForElement('css', '.search-form'));
+    $assert_session->addressEquals($address);
+  }
+
+}