diff --git a/core/modules/ckeditor5/ckeditor5.libraries.yml b/core/modules/ckeditor5/ckeditor5.libraries.yml
index d0908635c0..390d8ba230 100644
--- a/core/modules/ckeditor5/ckeditor5.libraries.yml
+++ b/core/modules/ckeditor5/ckeditor5.libraries.yml
@@ -27,7 +27,6 @@ drupal.ckeditor5:
     - core/ckeditor5.editorDecoupled
     - core/ckeditor5
     - editor/drupal.editor
-    - ckeditor5/drupal.ckeditor5.quickedit-temporary-work-around
     - ckeditor5/drupal.ckeditor5.stylesheets
     - core/drupalSettings
     - core/drupal.message
@@ -100,6 +99,12 @@ drupal.ckeditor5.filter.admin:
     - core/drupalSettings
     - core/drupal.message
 
+drupal.ckeditor5.stylesheets.warning:
+  drupalSettings:
+    ckeditor5:
+      ckeditor4_stylesheets: []
+
+
 admin:
   js:
     js/ckeditor5.admin.js: { }
diff --git a/core/modules/ckeditor5/ckeditor5.module b/core/modules/ckeditor5/ckeditor5.module
index c57091491b..6dddd24b91 100644
--- a/core/modules/ckeditor5/ckeditor5.module
+++ b/core/modules/ckeditor5/ckeditor5.module
@@ -357,7 +357,7 @@ function ckeditor5_library_info_alter(&$libraries, $extension) {
     ];
 
     $admin_theme = \Drupal::configFactory()->get('system.theme')->get('admin');
-    $admin_theme_info = \Drupal::service('theme_handler')->listInfo()[$admin_theme]->info;
+    $admin_theme_info = !empty($admin_theme) ? \Drupal::service('theme_handler')->listInfo()[$admin_theme]->info : [];
 
     $opt_out_ckeditor5_stylesheets = (isset($admin_theme_info['ckeditor5-stylesheets']) && $admin_theme_info['ckeditor5-info'] !== FALSE);
 
@@ -383,10 +383,16 @@ function ckeditor5_library_info_alter(&$libraries, $extension) {
         $base_theme = $base_theme_info['base_theme'] ?? FALSE;
       }
       if (!empty($ckeditor4_stylesheets)) {
-        $libraries['drupal.ckeditor5']['drupalSettings']['ckeditor5']['ckeditor4_stylesheets'] = $ckeditor4_stylesheets;
-        $libraries['drupal.ckeditor5.filter.admin']['drupalSettings']['ckeditor5']['ckeditor4_stylesheets'] = $ckeditor4_stylesheets;
+        $libraries['drupal.ckeditor5']['dependencies'][] = 'ckeditor5/drupal.ckeditor5.stylesheets.warning';
+        $libraries['drupal.ckeditor5.filter.admin']['dependencies'][] = 'ckeditor5/drupal.ckeditor5.stylesheets.warning';
+        $libraries['drupal.ckeditor5.stylesheets.warning']['drupalSettings']['ckeditor5']['ckeditor4_stylesheets'] = $ckeditor4_stylesheets;
       }
     }
+
+    $moduleHandler = \Drupal::service('module_handler');
+    if ($moduleHandler->moduleExists('quickedit')) {
+      $libraries['drupal.ckeditor5']['dependencies'][] = 'ckeditor5/drupal.ckeditor5.quickedit-temporary-work-around';
+    }
   }
 
   if ($extension === 'core') {
diff --git a/core/modules/ckeditor5/tests/src/Functional/CKEditor5QuickEditLibraryTest.php b/core/modules/ckeditor5/tests/src/Functional/CKEditor5QuickEditLibraryTest.php
new file mode 100644
index 0000000000..6d31fb43a5
--- /dev/null
+++ b/core/modules/ckeditor5/tests/src/Functional/CKEditor5QuickEditLibraryTest.php
@@ -0,0 +1,92 @@
+<?php
+
+namespace Drupal\Tests\ckeditor5\Functional;
+
+use Drupal\ckeditor5\Plugin\Editor\CKEditor5;
+use Drupal\editor\Entity\Editor;
+use Drupal\filter\Entity\FilterFormat;
+use Drupal\Tests\BrowserTestBase;
+use Drupal\user\RoleInterface;
+use Symfony\Component\Validator\ConstraintViolation;
+
+/**
+ * Tests that Quickedit-specific library loads when Quickedit is enabled.
+ *
+ * @group ckeditor5
+ * @group legacy
+ */
+class CKEditor5QuickEditLibraryTest extends BrowserTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected static $modules = [
+    'node',
+    'ckeditor5',
+    'quickedit',
+  ];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected $defaultTheme = 'stark';
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp(): void {
+    parent::setUp();
+
+    $filtered_html_format = FilterFormat::create([
+      'format' => 'llama',
+      'name' => 'Llama',
+      'filters' => [],
+      'roles' => [RoleInterface::AUTHENTICATED_ID],
+    ]);
+    $filtered_html_format->save();
+    $this->editor = Editor::create([
+      'format' => 'llama',
+      'editor' => 'ckeditor5',
+      'settings' => [
+        'toolbar' => [
+          'items' => [],
+        ],
+      ],
+    ]);
+    $this->editor->save();
+    $this->assertSame([], array_map(
+      function (ConstraintViolation $v) {
+        return (string) $v->getMessage();
+      },
+      iterator_to_array(CKEditor5::validatePair($this->editor, $filtered_html_format))
+    ));
+    // Create node type.
+    $this->drupalCreateContentType([
+      'type' => 'article',
+      'name' => 'Article',
+    ]);
+
+    $this->adminUser = $this->drupalCreateUser([
+      'create article content',
+      'edit own article content',
+      'use text format llama',
+    ]);
+    $this->drupalLogin($this->adminUser);
+  }
+
+  public function testQuickeditTemporaryWorkaround() {
+    $assert_session = $this->assertSession();
+
+    $this->expectDeprecation('Temporary work-around until https://www.drupal.org/project/drupal/issues/3196689 lands.');
+    /** @var \Drupal\Core\Extension\ThemeInstallerInterface $theme_installer */
+    $theme_installer = \Drupal::service('theme_installer');
+    // Install a theme which has an absolute external CSS URL.
+    $theme_installer->install(['test_ckeditor_stylesheets_relative']);
+    $this->config('system.theme')->set('default', 'test_ckeditor_stylesheets_relative')->save();
+    $this->config('system.theme')->set('admin', 'stark')->save();
+
+    $this->drupalGet('node/add/article');
+    $assert_session->responseContains('css/quickedit-override.css');
+  }
+
+}
diff --git a/core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditorStylesheetsWarningTest.php b/core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditorStylesheetsWarningTest.php
index c9ebbcd373..d743b1d38d 100644
--- a/core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditorStylesheetsWarningTest.php
+++ b/core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditorStylesheetsWarningTest.php
@@ -15,11 +15,15 @@ class CKEditorStylesheetsWarningTest extends CKEditor5TestBase {
    */
   protected function setUp(): void {
     parent::setUp();
+  }
+
+  public function installThemeThatTriggersWarning() {
     $theme_installer = \Drupal::service('theme_installer');
     $theme_installer->install(['test_ckeditor_stylesheets_without_5']);
     $this->config('system.theme')->set('default', 'test_ckeditor_stylesheets_without_5')->save();
     $theme_installer->install(['stark']);
     $this->config('system.theme')->set('admin', 'stark')->save();
+    \Drupal::service('theme_handler')->refreshInfo();
   }
 
   /**
@@ -30,7 +34,10 @@ public function testWarningFilterUI() {
     $assert_session = $this->assertSession();
     $this->addNewTextFormat($page, $assert_session);
     $this->drupalGet('admin/config/content/formats/manage/ckeditor5');
-    $assert_session->waitForText('There are CKEditor 4 stylesheets without equivalents');
+    $this->assertFalse($assert_session->waitForText('There are CKEditor 4 stylesheets without equivalents', 5000));
+    $this->installThemeThatTriggersWarning();
+    $this->drupalGet('admin/config/content/formats/manage/ckeditor5');
+    $this->assertTrue($assert_session->waitForText('There are CKEditor 4 stylesheets without equivalents'));
   }
 
   /**
@@ -41,7 +48,13 @@ public function testWarningEditorInstance() {
     $assert_session = $this->assertSession();
     $this->addNewTextFormat($page, $assert_session);
     $this->drupalGet('node/add');
-    $assert_session->waitForText('There are CKEditor 4 stylesheets that may need CKeditor 5 equivalents.');
+    $this->assertFalse($assert_session->waitForText('There are CKEditor 4 stylesheets that may need CKeditor 5 equivalents.', 5000));
+    $this->installThemeThatTriggersWarning();
+
+    // Go somewhere other than node/add to ensure hook_libraries is updated.
+    $this->drupalGet('admin/config/content/formats/manage/ckeditor5');
+    $this->drupalGet('node/add');
+    $this->assertTrue($assert_session->waitForText('There are CKEditor 4 stylesheets that may need CKeditor 5 equivalents.'));
   }
 
 }