Issue #3523705 by amateescu, rkoller, poker10: InvalidComponentException when...

Issue #3523705 by amateescu, rkoller, poker10: InvalidComponentException when workspaces ui is installed

core/modules/navigation/src/WorkspacesLazyBuilder.php

@@ -59,6 +59,9 @@ public function renderNavigationLinks(): array {
           'title' => $active_workspace ? $active_workspace->label() : $this->t('Live'),
           'url' => $url,
           'class' => 'workspaces',
+          'icon' => [
+            'icon_id' => 'workspaces',
+          ],
         ],
       ],
       '#attached' => [

core/modules/navigation/tests/src/Functional/NavigationWorkspacesUiTest.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\Tests\navigation\Functional;
+
+use Drupal\Tests\BrowserTestBase;
+
+/**
+ * Tests for \Drupal\navigation\WorkspacesLazyBuilder.
+ *
+ * @group navigation
+ */
+class NavigationWorkspacesUiTest extends BrowserTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected static $modules = ['navigation', 'workspaces_ui'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected $defaultTheme = 'stark';
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp(): void {
+    parent::setUp();
+
+    $admin_user = $this->drupalCreateUser([
+      'access navigation',
+      'administer workspaces',
+    ]);
+    $this->drupalLogin($admin_user);
+  }
+
+  /**
+   * Tests the Workspaces button in the navigation bar.
+   */
+  public function testWorkspacesNavigationButton(): void {
+    $this->drupalGet('<front>');
+    $this->assertSession()->statusCodeEquals(200);
+    $this->assertSession()->elementAttributeContains('css', 'a.toolbar-button--icon--workspaces svg', 'width', '20');
+    $this->assertSession()->elementAttributeContains('css', 'a.toolbar-button--icon--workspaces svg', 'class', 'toolbar-button__icon');
+  }
+
+}