From 5b0cd33e9afec35514410ce2dbdc76516da6bd11 Mon Sep 17 00:00:00 2001
From: Lauri Eskola <lauri.eskola@acquia.com>
Date: Fri, 26 Aug 2022 21:08:10 +0300
Subject: [PATCH] Issue #3270734 by Wim Leers, longwave, andregp, bnjmnm:
 Update Editor + CKEditor 5 module to not use CKEditor 4 in tests

(cherry picked from commit f09840a74b9affe5a6e3e85f668d9eadec74ea85)
---
 .../CKEditor5CKEditor4Compatibility.php       | 22 +++++-
 .../ckeditor5/src/SmartDefaultSettings.php    |  5 +-
 .../src/FunctionalJavascript/AdminUiTest.php  |  8 +-
 .../CKEditor5AllowedTagsTest.php              | 76 +++++++-----------
 .../src/Kernel/SmartDefaultSettingsTest.php   | 77 +++++++++++--------
 core/modules/editor/src/Entity/Editor.php     | 12 ++-
 .../install/editor.editor.private_images.yml  | 21 +----
 .../src/Plugin/Editor/UnicornEditor.php       | 16 ++++
 .../src/Functional/EditorDialogAccessTest.php | 19 +----
 .../EditorPrivateFileReferenceFilterTest.php  |  6 +-
 .../FunctionalJavascript/EditorAdminTest.php  | 20 ++---
 11 files changed, 138 insertions(+), 144 deletions(-)
 rename core/modules/{ckeditor5 => ckeditor}/tests/src/FunctionalJavascript/CKEditor5CKEditor4Compatibility.php (87%)

diff --git a/core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditor5CKEditor4Compatibility.php b/core/modules/ckeditor/tests/src/FunctionalJavascript/CKEditor5CKEditor4Compatibility.php
similarity index 87%
rename from core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditor5CKEditor4Compatibility.php
rename to core/modules/ckeditor/tests/src/FunctionalJavascript/CKEditor5CKEditor4Compatibility.php
index b6e4b42f674..aa3c14968f0 100644
--- a/core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditor5CKEditor4Compatibility.php
+++ b/core/modules/ckeditor/tests/src/FunctionalJavascript/CKEditor5CKEditor4Compatibility.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Drupal\Tests\ckeditor5\FunctionalJavascript;
+namespace Drupal\Tests\ckeditor\FunctionalJavascript;
 
 use Drupal\ckeditor5\Plugin\Editor\CKEditor5;
 use Drupal\Core\Entity\Entity\EntityFormDisplay;
@@ -8,30 +8,46 @@ use Drupal\editor\Entity\Editor;
 use Drupal\field\Entity\FieldConfig;
 use Drupal\field\Entity\FieldStorageConfig;
 use Drupal\filter\Entity\FilterFormat;
+use Drupal\FunctionalJavascriptTests\WebDriverTestBase;
 use Symfony\Component\Validator\ConstraintViolation;
 
 /**
  * Ensures that CKEditor 5 can be used on the same page with CKEditor 4.
  *
- * @group ckeditor5
+ * @group ckeditor
  * @internal
  */
-class CKEditor5CKEditor4Compatibility extends CKEditor5TestBase {
+class CKEditor5CKEditor4Compatibility extends WebDriverTestBase {
 
   /**
    * {@inheritdoc}
    */
   protected static $modules = [
     'ckeditor',
+    'node',
+    'ckeditor5',
     'ckeditor5_test',
   ];
 
+  /**
+   * {@inheritdoc}
+   */
+  protected $defaultTheme = 'stark';
+
   /**
    * {@inheritdoc}
    */
   protected function setUp(): void {
     parent::setUp();
 
+    $this->drupalCreateContentType(['type' => 'page']);
+
+    $this->drupalLogin($this->drupalCreateUser([
+      'administer filters',
+      'create page content',
+      'edit own page content',
+    ]));
+
     $current_user_roles = $this->loggedInUser->getRoles(TRUE);
 
     // Create text format, text editor and text fields for CKEditor 5 and 4.
diff --git a/core/modules/ckeditor5/src/SmartDefaultSettings.php b/core/modules/ckeditor5/src/SmartDefaultSettings.php
index b5f29697fde..08db67c9a14 100644
--- a/core/modules/ckeditor5/src/SmartDefaultSettings.php
+++ b/core/modules/ckeditor5/src/SmartDefaultSettings.php
@@ -149,10 +149,13 @@ final class SmartDefaultSettings {
     // if it exists.
     $old_editor = $editor->id() ? Editor::load($editor->id()) : NULL;
     $old_editor_restrictions = $old_editor ? HTMLRestrictions::fromTextFormat($old_editor->getFilterFormat()) : HTMLRestrictions::emptySet();
+    // @todo Remove in https://www.drupal.org/project/drupal/issues/3245351
+    if ($old_editor) {
+      $editor->setImageUploadSettings($old_editor->getImageUploadSettings());
+    }
     if ($old_editor && $old_editor->getEditor() === 'ckeditor') {
       [$upgraded_settings, $messages] = $this->createSettingsFromCKEditor4($old_editor->getSettings(), HTMLRestrictions::fromTextFormat($old_editor->getFilterFormat()));
       $editor->setSettings($upgraded_settings);
-      $editor->setImageUploadSettings($old_editor->getImageUploadSettings());
       // *Before* determining which elements are still needed for this text
       // format, ensure that all already enabled plugins that are configurable
       // have valid settings.
diff --git a/core/modules/ckeditor5/tests/src/FunctionalJavascript/AdminUiTest.php b/core/modules/ckeditor5/tests/src/FunctionalJavascript/AdminUiTest.php
index 2d237aaeb45..2de19d18138 100644
--- a/core/modules/ckeditor5/tests/src/FunctionalJavascript/AdminUiTest.php
+++ b/core/modules/ckeditor5/tests/src/FunctionalJavascript/AdminUiTest.php
@@ -17,7 +17,7 @@ class AdminUiTest extends CKEditor5TestBase {
    */
   protected static $modules = [
     'media_library',
-    'ckeditor',
+    'editor_test',
     'ckeditor5_incompatible_filter_test',
   ];
 
@@ -28,7 +28,7 @@ class AdminUiTest extends CKEditor5TestBase {
     $page = $this->getSession()->getPage();
     $assert_session = $this->assertSession();
     $this->addNewTextFormat($page, $assert_session);
-    $this->addNewTextFormat($page, $assert_session, 'ckeditor');
+    $this->addNewTextFormat($page, $assert_session, 'unicorn');
 
     $this->drupalGet('admin/config/content/formats/manage/ckeditor5');
     $number_ajax_instances_before = $this->getSession()->evaluateScript('Drupal.ajax.instances.length');
@@ -47,7 +47,7 @@ class AdminUiTest extends CKEditor5TestBase {
 
     // Perform the same steps as above with CKEditor, and confirm AJAX callbacks
     // are not triggered on settings changes.
-    $this->drupalGet('admin/config/content/formats/manage/ckeditor');
+    $this->drupalGet('admin/config/content/formats/manage/unicorn');
     $number_ajax_instances_before = $this->getSession()->evaluateScript('Drupal.ajax.instances.length');
 
     // Enable media embed to confirm a format not using CKEditor 5 will not
@@ -105,7 +105,7 @@ class AdminUiTest extends CKEditor5TestBase {
   public function testUnavailableFiltersHiddenWhenSwitching() {
     $page = $this->getSession()->getPage();
     $assert_session = $this->assertSession();
-    $this->createNewTextFormat($page, $assert_session, 'ckeditor');
+    $this->createNewTextFormat($page, $assert_session, 'unicorn');
     $assert_session->assertWaitOnAjaxRequest();
     $assert_session->pageTextNotContains('Filter settings');
 
diff --git a/core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditor5AllowedTagsTest.php b/core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditor5AllowedTagsTest.php
index 540f54ada51..86265f45c41 100644
--- a/core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditor5AllowedTagsTest.php
+++ b/core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditor5AllowedTagsTest.php
@@ -22,7 +22,7 @@ class CKEditor5AllowedTagsTest extends CKEditor5TestBase {
    */
   protected static $modules = [
     'node',
-    'ckeditor',
+    'editor_test',
     'ckeditor5',
     'media',
     'media_library',
@@ -37,18 +37,20 @@ class CKEditor5AllowedTagsTest extends CKEditor5TestBase {
   protected $allowedElements = '<br> <p> <h2> <h3> <h4> <h5> <h6> <strong> <em>';
 
   /**
-   * The default allowed elements when updating a non-CKEditor 5 editor.
+   * The default allowed elements for filter_html's "allowed_html" setting.
+   *
+   * @see \Drupal\filter\Plugin\Filter\FilterHtml
    *
    * @var string
    */
-  protected $defaultElementsWhenUpdatingNotCkeditor5 = '<a href hreflang> <em> <strong> <cite> <blockquote cite> <code> <ul type> <ol start type> <li> <dl> <dt> <dd> <h2 id> <h3 id> <h4 id> <h5 id> <h6 id> <img src alt data-entity-type data-entity-uuid>';
+  protected $defaultElementsWhenUpdatingNotCkeditor5 = "<a href hreflang> <em> <strong> <cite> <blockquote cite> <code> <ul type> <ol start type='1 A I'> <li> <dl> <dt> <dd> <h2 id='jump-*'> <h3 id> <h4 id> <h5 id> <h6 id>";
 
   /**
-   * The expected allowed elements after updating to CKEditor5.
+   * The expected allowed elements after updating to CKEditor 5.
    *
    * @var string
    */
-  protected $defaultElementsAfterUpdatingToCkeditor5 = '<br> <p> <h2 id> <h3 id> <h4 id> <h5 id> <h6 id> <cite> <dl> <dt> <dd> <img src alt data-entity-type data-entity-uuid> <a hreflang href> <blockquote cite> <ul type> <ol type start> <strong> <em> <code> <li>';
+  protected $defaultElementsAfterUpdatingToCkeditor5 = '<br> <p> <h2 id="jump-*"> <h3 id> <h4 id> <h5 id> <h6 id> <cite> <dl> <dt> <dd> <a hreflang href> <blockquote cite> <ul type> <ol type="1 A I" start> <strong> <em> <code> <li>';
 
   /**
    * Test enabling CKEditor 5 in a way that triggers validation.
@@ -60,8 +62,8 @@ class CKEditor5AllowedTagsTest extends CKEditor5TestBase {
     $incompatible_filter_name = 'filters[filter_incompatible][status]';
     $filter_warning = 'CKEditor 5 only works with HTML-based text formats. The "A TYPE_MARKUP_LANGUAGE filter incompatible with CKEditor 5" (filter_incompatible) filter implies this text format is not HTML anymore.';
 
-    $this->createNewTextFormat($page, $assert_session, 'ckeditor');
-    $page->selectFieldOption('editor[editor]', 'ckeditor');
+    $this->createNewTextFormat($page, $assert_session, 'unicorn');
+    $page->selectFieldOption('editor[editor]', 'unicorn');
     $assert_session->assertWaitOnAjaxRequest();
     $page->checkField('filters[filter_html][status]');
     $page->checkField($incompatible_filter_name);
@@ -81,31 +83,16 @@ class CKEditor5AllowedTagsTest extends CKEditor5TestBase {
   }
 
   /**
-   * Tests that when image uploads are enabled in CKEditor 4, they remain in 5.
+   * Tests that when image uploads were enabled, they remain enabled.
    */
   public function testImageUploadsRemainEnabled(): void {
     FilterFormat::create([
-      'format' => 'cke4_image_uploads',
-      'name' => 'CKEditor 4, image uploads',
+      'format' => 'editor_with_image_uploads',
+      'name' => 'Text Editor with image uploads enabled',
     ])->save();
     Editor::create([
-      'format' => 'cke4_image_uploads',
-      'editor' => 'ckeditor',
-      'settings' => [
-        'toolbar' => [
-          'rows' => [
-            0 => [
-              [
-                'name' => 'Media',
-                'items' => [
-                  'DrupalImage',
-                ],
-              ],
-            ],
-          ],
-        ],
-        'plugins' => [],
-      ],
+      'format' => 'editor_with_image_uploads',
+      'editor' => 'unicorn',
       'image_upload' => [
         'status' => TRUE,
         'scheme' => 'public',
@@ -122,13 +109,19 @@ class CKEditor5AllowedTagsTest extends CKEditor5TestBase {
     $assert_session = $this->assertSession();
 
     // Assert that image uploads are enabled initially.
-    $this->drupalGet('admin/config/content/formats/manage/cke4_image_uploads');
+    $this->drupalGet('admin/config/content/formats/manage/editor_with_image_uploads');
     $this->assertTrue($page->hasCheckedField('Enable image uploads'));
 
     // Switch the text format to CKEditor 5.
     $page->selectFieldOption('editor[editor]', 'ckeditor5');
     $assert_session->assertWaitOnAjaxRequest();
 
+    // Enable the image toolbar item. This does NOT enable image uploads: it
+    // triggers the image upload settings form to become visible, to allow the
+    // image upload status to be checked.
+    $this->triggerKeyUp('.ckeditor5-toolbar-item-uploadImage', 'ArrowDown');
+    $assert_session->assertWaitOnAjaxRequest();
+
     // Assert that image uploads are still enabled.
     $this->assertTrue($page->hasCheckedField('Enable image uploads'));
   }
@@ -140,7 +133,7 @@ class CKEditor5AllowedTagsTest extends CKEditor5TestBase {
     $page = $this->getSession()->getPage();
     $assert_session = $this->assertSession();
 
-    $this->createNewTextFormat($page, $assert_session, 'ckeditor');
+    $this->createNewTextFormat($page, $assert_session, 'unicorn');
     $assert_session->assertWaitOnAjaxRequest();
 
     // Enable the HTML filter.
@@ -148,15 +141,15 @@ class CKEditor5AllowedTagsTest extends CKEditor5TestBase {
     $page->checkField('filters[filter_html][status]');
     $assert_session->assertWaitOnAjaxRequest();
 
-    // Confirm the allowed HTML tags are the defaults for non-Ckeditor5 editors.
+    // Confirm the allowed HTML tags are the defaults initially.
     $this->assertHtmlEsqueFieldValueEquals('filters[filter_html][settings][allowed_html]', $this->defaultElementsWhenUpdatingNotCkeditor5);
 
     $this->saveNewTextFormat($page, $assert_session);
-    $assert_session->pageTextContains('Added text format ckeditor');
+    $assert_session->pageTextContains('Added text format unicorn');
 
     // Return to the config form to confirm that switching text editors on
     // existing formats will properly switch allowed tags.
-    $this->drupalGet('admin/config/content/formats/manage/ckeditor');
+    $this->drupalGet('admin/config/content/formats/manage/unicorn');
     $assert_session->assertWaitOnAjaxRequest();
     $this->assertHtmlEsqueFieldValueEquals('filters[filter_html][settings][allowed_html]', $this->defaultElementsWhenUpdatingNotCkeditor5);
 
@@ -167,24 +160,7 @@ class CKEditor5AllowedTagsTest extends CKEditor5TestBase {
 
     $page->pressButton('Save configuration');
 
-    $assert_session->pageTextContains('The Image upload toolbar item requires image uploads to be enabled.');
-    $page->clickLink('Image Upload');
-    $assert_session->waitForText('Enable image uploads');
-    $this->assertTrue($page->hasUncheckedField('editor[settings][plugins][ckeditor5_imageUpload][status]'));
-    $page->checkField('editor[settings][plugins][ckeditor5_imageUpload][status]');
-    $assert_session->assertWaitOnAjaxRequest();
-    $page->pressButton('Save configuration');
-    $this->assertSession()->pageTextContains('The following attribute(s) are already supported by enabled plugins and should not be added to the Source Editing "Manually editable HTML tags" field: Image (<img src alt data-entity-uuid data-entity-type>)');
-
-    $assert_session->assertWaitOnAjaxRequest();
-    $assert_session->waitForText('Manually editable HTML tags');
-    $source_edit_tags_field = $assert_session->fieldExists('editor[settings][plugins][ckeditor5_sourceEditing][allowed_tags]');
-    $source_edit_tags_field_value = $source_edit_tags_field->getValue();
-    $source_edit_tags_field->setValue(str_replace('<img src alt data-entity-type data-entity-uuid>', '', $source_edit_tags_field_value));
-    $assert_session->assertWaitOnAjaxRequest();
-    $page->pressButton('Save configuration');
-
-    $assert_session->pageTextContains('The text format ckeditor has been updated');
+    $assert_session->pageTextContains('The text format unicorn has been updated');
   }
 
   /**
diff --git a/core/modules/ckeditor5/tests/src/Kernel/SmartDefaultSettingsTest.php b/core/modules/ckeditor5/tests/src/Kernel/SmartDefaultSettingsTest.php
index 16ad3e29a09..d13ace4a201 100644
--- a/core/modules/ckeditor5/tests/src/Kernel/SmartDefaultSettingsTest.php
+++ b/core/modules/ckeditor5/tests/src/Kernel/SmartDefaultSettingsTest.php
@@ -23,6 +23,17 @@ class SmartDefaultSettingsTest extends KernelTestBase {
   use SchemaCheckTestTrait;
   use CKEditor5ValidationTestTrait;
 
+  /**
+   * Exempt from strict schema checking, because using CKEditor 4.
+   *
+   * The updated Text Format & Text Editors are explicitly checked.
+   *
+   * @see \Drupal\Core\Config\Development\ConfigSchemaChecker
+   *
+   * @var bool
+   */
+  protected $strictConfigSchema = FALSE;
+
   /**
    * The manager for "CKEditor 5 plugin" plugins.
    *
@@ -55,8 +66,6 @@ class SmartDefaultSettingsTest extends KernelTestBase {
    * {@inheritdoc}
    */
   protected static $modules = [
-    'ckeditor',
-    'ckeditor_test',
     'ckeditor5',
     'editor',
     'filter',
@@ -90,17 +99,17 @@ class SmartDefaultSettingsTest extends KernelTestBase {
       ->save();
     Editor::create(
       Yaml::parseFile('core/modules/ckeditor5/tests/fixtures/ckeditor4_config/editor.editor.full_html.yml')
-    )->save();
+    )->setSyncing(TRUE)->save();
 
     $basic_html_format = Yaml::parseFile('core/modules/ckeditor5/tests/fixtures/ckeditor4_config/filter.format.basic_html.yml');
-    FilterFormat::create($basic_html_format)->save();
+    FilterFormat::create($basic_html_format)->setSyncing(TRUE)->save();
     Editor::create(
       Yaml::parseFile('core/modules/ckeditor5/tests/fixtures/ckeditor4_config/editor.editor.basic_html.yml')
-    )->save();
+    )->setSyncing(TRUE)->save();
 
     FilterFormat::create(
       Yaml::parseFile('core/modules/ckeditor5/tests/fixtures/ckeditor4_config/filter.format.restricted_html.yml')
-    )->save();
+    )->setSyncing(TRUE)->save();
 
     $allowed_html_parents = ['filters', 'filter_html', 'settings', 'allowed_html'];
     $current_value = NestedArray::getValue($basic_html_format, $allowed_html_parents);
@@ -109,58 +118,58 @@ class SmartDefaultSettingsTest extends KernelTestBase {
     $basic_html_format_without_h4_h6['name'] .= ' (without H4 and H6)';
     $basic_html_format_without_h4_h6['format'] = 'basic_html_without_h4_h6';
     NestedArray::setValue($basic_html_format_without_h4_h6, $allowed_html_parents, $new_value);
-    FilterFormat::create($basic_html_format_without_h4_h6)->save();
+    FilterFormat::create($basic_html_format_without_h4_h6)->setSyncing(TRUE)->save();
     Editor::create(
       ['format' => 'basic_html_without_h4_h6']
       +
       Yaml::parseFile('core/modules/ckeditor5/tests/fixtures/ckeditor4_config/editor.editor.basic_html.yml')
-    )->save();
+    )->setSyncing(TRUE)->save();
 
     $new_value = str_replace(['<h2 id> ', '<h3 id> ', '<h4 id> ', '<h5 id> ', '<h6 id> '], '', $current_value);
     $basic_html_format_without_headings = $basic_html_format;
     $basic_html_format_without_headings['name'] .= ' (without H*)';
     $basic_html_format_without_headings['format'] = 'basic_html_without_headings';
     NestedArray::setValue($basic_html_format_without_headings, $allowed_html_parents, $new_value);
-    FilterFormat::create($basic_html_format_without_headings)->save();
+    FilterFormat::create($basic_html_format_without_headings)->setSyncing(TRUE)->save();
     Editor::create(
       ['format' => 'basic_html_without_headings']
       +
       Yaml::parseFile('core/modules/ckeditor5/tests/fixtures/ckeditor4_config/editor.editor.basic_html.yml')
-    )->save();
+    )->setSyncing(TRUE)->save();
 
     $basic_html_format_with_pre = $basic_html_format;
     $basic_html_format_with_pre['name'] .= ' (with <pre>)';
     $basic_html_format_with_pre['format'] = 'basic_html_with_pre';
     NestedArray::setValue($basic_html_format_with_pre, $allowed_html_parents, $current_value . ' <pre>');
-    FilterFormat::create($basic_html_format_with_pre)->save();
+    FilterFormat::create($basic_html_format_with_pre)->setSyncing(TRUE)->save();
     Editor::create(
       ['format' => 'basic_html_with_pre']
       +
       Yaml::parseFile('core/modules/ckeditor5/tests/fixtures/ckeditor4_config/editor.editor.basic_html.yml')
-    )->save();
+    )->setSyncing(TRUE)->save();
 
     $basic_html_format_with_h1 = $basic_html_format;
     $basic_html_format_with_h1['name'] .= ' (with <h1>)';
     $basic_html_format_with_h1['format'] = 'basic_html_with_h1';
     NestedArray::setValue($basic_html_format_with_h1, $allowed_html_parents, $current_value . ' <h1>');
-    FilterFormat::create($basic_html_format_with_h1)->save();
+    FilterFormat::create($basic_html_format_with_h1)->setSyncing(TRUE)->save();
     Editor::create(
       ['format' => 'basic_html_with_h1']
       +
       Yaml::parseFile('core/modules/ckeditor5/tests/fixtures/ckeditor4_config/editor.editor.basic_html.yml')
-    )->save();
+    )->setSyncing(TRUE)->save();
 
     $new_value = str_replace('<p>', '<p class="text-align-center text-align-justify">', $current_value);
     $basic_html_format_with_alignable_p = $basic_html_format;
     $basic_html_format_with_alignable_p['name'] .= ' (with alignable paragraph support)';
     $basic_html_format_with_alignable_p['format'] = 'basic_html_with_alignable_p';
     NestedArray::setValue($basic_html_format_with_alignable_p, $allowed_html_parents, $new_value);
-    FilterFormat::create($basic_html_format_with_alignable_p)->save();
+    FilterFormat::create($basic_html_format_with_alignable_p)->setSyncing(TRUE)->save();
     Editor::create(
       ['format' => 'basic_html_with_alignable_p']
       +
       Yaml::parseFile('core/modules/ckeditor5/tests/fixtures/ckeditor4_config/editor.editor.basic_html.yml')
-    )->save();
+    )->setSyncing(TRUE)->save();
 
     $basic_html_format_with_media_embed = $basic_html_format;
     $basic_html_format_with_media_embed['name'] .= ' (with Media Embed support)';
@@ -169,7 +178,7 @@ class SmartDefaultSettingsTest extends KernelTestBase {
     $basic_html_format_with_media_embed['filters']['media_embed'] = ['status' => TRUE];
     $new_value = $current_value . ' <drupal-media data-entity-type data-entity-uuid data-align data-caption alt>';
     NestedArray::setValue($basic_html_format_with_media_embed, $allowed_html_parents, $new_value);
-    FilterFormat::create($basic_html_format_with_media_embed)->save();
+    FilterFormat::create($basic_html_format_with_media_embed)->setSyncing(TRUE)->save();
     $basic_html_editor_with_media_embed = Editor::create(
       ['format' => 'basic_html_with_media_embed']
       +
@@ -180,7 +189,7 @@ class SmartDefaultSettingsTest extends KernelTestBase {
     // pre-existing toolbar item group labeled "Media".
     $settings['toolbar']['rows'][0][3]['items'][] = 'DrupalMediaLibrary';
     $basic_html_editor_with_media_embed->setSettings($settings);
-    $basic_html_editor_with_media_embed->save();
+    $basic_html_editor_with_media_embed->setSyncing(TRUE)->save();
 
     $basic_html_format_with_media_embed_view_mode_invalid = $basic_html_format_with_media_embed;
     $basic_html_format_with_media_embed_view_mode_invalid['name'] = ' (with Media Embed support, view mode enabled but no view modes configured)';
@@ -188,7 +197,7 @@ class SmartDefaultSettingsTest extends KernelTestBase {
     $current_value_media_embed = NestedArray::getValue($basic_html_format_with_media_embed, $allowed_html_parents);
     $new_value = str_replace('<drupal-media data-entity-type data-entity-uuid data-align data-caption alt>', '<drupal-media data-entity-type data-entity-uuid data-align data-caption alt data-view-mode>', $current_value_media_embed);
     NestedArray::setValue($basic_html_format_with_media_embed_view_mode_invalid, $allowed_html_parents, $new_value);
-    FilterFormat::create($basic_html_format_with_media_embed_view_mode_invalid)->save();
+    FilterFormat::create($basic_html_format_with_media_embed_view_mode_invalid)->setSyncing(TRUE)->save();
     $basic_html_editor_with_media_embed_view_mode_enabled_no_view_modes_configured = Editor::create(
       ['format' => 'basic_html_with_media_embed_view_mode_enabled_no_view_modes_configured']
       +
@@ -199,24 +208,24 @@ class SmartDefaultSettingsTest extends KernelTestBase {
     // pre-existing toolbar item group labeled "Media".
     $settings['toolbar']['rows'][0][3]['items'][] = 'DrupalMediaLibrary';
     $basic_html_editor_with_media_embed_view_mode_enabled_no_view_modes_configured->setSettings($settings);
-    $basic_html_editor_with_media_embed_view_mode_enabled_no_view_modes_configured->save();
+    $basic_html_editor_with_media_embed_view_mode_enabled_no_view_modes_configured->setSyncing(TRUE)->save();
 
     $new_value = str_replace('<img src alt height width data-entity-type data-entity-uuid data-align data-caption>', '<img src alt height width data-*>', $current_value);
     $basic_html_format_with_any_data_attr = $basic_html_format;
     $basic_html_format_with_any_data_attr['name'] .= ' (with any data-* attribute on images)';
     $basic_html_format_with_any_data_attr['format'] = 'basic_html_with_any_data_attr';
     NestedArray::setValue($basic_html_format_with_any_data_attr, $allowed_html_parents, $new_value);
-    FilterFormat::create($basic_html_format_with_any_data_attr)->save();
+    FilterFormat::create($basic_html_format_with_any_data_attr)->setSyncing(TRUE)->save();
     Editor::create(
       ['format' => 'basic_html_with_any_data_attr']
       +
       Yaml::parseFile('core/modules/ckeditor5/tests/fixtures/ckeditor4_config/editor.editor.basic_html.yml')
-    )->save();
+    )->setSyncing(TRUE)->save();
 
     $basic_html_format_with_media_embed_view_mode_enabled_two_view_modes_configured = $basic_html_format_with_media_embed_view_mode_invalid;
     $basic_html_format_with_media_embed_view_mode_enabled_two_view_modes_configured['name'] = ' (with Media Embed support, view mode enabled and two view modes configured )';
     $basic_html_format_with_media_embed_view_mode_enabled_two_view_modes_configured['format'] = 'basic_html_with_media_embed_view_mode_enabled_two_view_modes_configured';
-    FilterFormat::create($basic_html_format_with_media_embed_view_mode_enabled_two_view_modes_configured)->save();
+    FilterFormat::create($basic_html_format_with_media_embed_view_mode_enabled_two_view_modes_configured)->setSyncing(TRUE)->save();
     $basic_html_editor_with_media_embed_view_mode_enabled_two_view_modes_configured = Editor::create(
       ['format' => 'basic_html_with_media_embed_view_mode_enabled_two_view_modes_configured']
       +
@@ -227,21 +236,21 @@ class SmartDefaultSettingsTest extends KernelTestBase {
     // pre-existing toolbar item group labeled "Media".
     $settings['toolbar']['rows'][0][3]['items'][] = 'DrupalMediaLibrary';
     $basic_html_editor_with_media_embed_view_mode_enabled_two_view_modes_configured->setSettings($settings);
-    $basic_html_editor_with_media_embed_view_mode_enabled_two_view_modes_configured->save();
+    $basic_html_editor_with_media_embed_view_mode_enabled_two_view_modes_configured->setSyncing(TRUE)->save();
     EntityViewMode::create([
       'id' => 'media.view_mode_1',
       'targetEntityType' => 'media',
       'status' => TRUE,
       'enabled' => TRUE,
       'label' => 'View Mode 1',
-    ])->save();
+    ])->setSyncing(TRUE)->save();
     EntityViewMode::create([
       'id' => 'media.view_mode_2',
       'targetEntityType' => 'media',
       'status' => TRUE,
       'enabled' => TRUE,
       'label' => 'View Mode 2',
-    ])->save();
+    ])->setSyncing(TRUE)->save();
     $filter_format = FilterFormat::load('basic_html_with_media_embed_view_mode_enabled_two_view_modes_configured');
     $filter_format->setFilterConfig('media_embed', [
       'status' => TRUE,
@@ -253,7 +262,7 @@ class SmartDefaultSettingsTest extends KernelTestBase {
           'view_mode_2' => 'view_mode_2',
         ],
       ],
-    ])->save();
+    ])->setSyncing(TRUE)->save();
 
     $filter_plugin_manager = $this->container->get('plugin.manager.filter');
     FilterFormat::create([
@@ -265,12 +274,12 @@ class SmartDefaultSettingsTest extends KernelTestBase {
           'settings' => $filter_plugin_manager->getDefinition('filter_html')['settings'],
         ],
       ],
-    ])->save();
+    ])->setSyncing(TRUE)->save();
 
     FilterFormat::create([
       'format' => 'cke4_plugins_with_settings',
       'name' => 'All CKEditor 4 core plugins with settings',
-    ])->save();
+    ])->setSyncing(TRUE)->save();
     Editor::create([
       'format' => 'cke4_plugins_with_settings',
       'editor' => 'ckeditor',
@@ -310,7 +319,7 @@ class SmartDefaultSettingsTest extends KernelTestBase {
           ],
         ],
       ],
-    ])->save();
+    ])->setSyncing(TRUE)->save();
 
     FilterFormat::create([
       'format' => 'cke4_stylescombo_span',
@@ -323,7 +332,7 @@ class SmartDefaultSettingsTest extends KernelTestBase {
           ] + $filter_plugin_manager->getDefinition('filter_html')['settings'],
         ],
       ],
-    ])->save();
+    ])->setSyncing(TRUE)->save();
     Editor::create([
       'format' => 'cke4_stylescombo_span',
       'editor' => 'ckeditor',
@@ -346,12 +355,12 @@ class SmartDefaultSettingsTest extends KernelTestBase {
           ],
         ],
       ],
-    ])->save();
+    ])->setSyncing(TRUE)->save();
 
     FilterFormat::create([
       'format' => 'cke4_contrib_plugins_now_in_core',
       'name' => 'All CKEditor 4 contrib plugins now in core',
-    ])->save();
+    ])->setSyncing(TRUE)->save();
     Editor::create([
       'format' => 'cke4_contrib_plugins_now_in_core',
       'editor' => 'ckeditor',
@@ -371,7 +380,7 @@ class SmartDefaultSettingsTest extends KernelTestBase {
         ],
         'plugins' => [],
       ],
-    ])->save();
+    ])->setSyncing(TRUE)->save();
   }
 
   /**
diff --git a/core/modules/editor/src/Entity/Editor.php b/core/modules/editor/src/Entity/Editor.php
index 5d60313a427..fc5f632d036 100644
--- a/core/modules/editor/src/Entity/Editor.php
+++ b/core/modules/editor/src/Entity/Editor.php
@@ -2,6 +2,7 @@
 
 namespace Drupal\editor\Entity;
 
+use Drupal\Component\Plugin\Exception\PluginNotFoundException;
 use Drupal\Core\Config\Entity\ConfigEntityBase;
 use Drupal\editor\EditorInterface;
 
@@ -90,8 +91,15 @@ class Editor extends ConfigEntityBase implements EditorInterface {
   public function __construct(array $values, $entity_type) {
     parent::__construct($values, $entity_type);
 
-    $plugin = $this->editorPluginManager()->createInstance($this->editor);
-    $this->settings += $plugin->getDefaultSettings();
+    try {
+      $plugin = $this->editorPluginManager()->createInstance($this->editor);
+      $this->settings += $plugin->getDefaultSettings();
+    }
+    catch (PluginNotFoundException $e) {
+      // When a Text Editor plugin has gone missing, still allow the Editor
+      // config entity to be constructed. The only difference is that default
+      // settings are not added.
+    }
   }
 
   /**
diff --git a/core/modules/editor/tests/editor_private_test/config/install/editor.editor.private_images.yml b/core/modules/editor/tests/editor_private_test/config/install/editor.editor.private_images.yml
index b8a536708d9..c5a3f9e9212 100644
--- a/core/modules/editor/tests/editor_private_test/config/install/editor.editor.private_images.yml
+++ b/core/modules/editor/tests/editor_private_test/config/install/editor.editor.private_images.yml
@@ -4,26 +4,9 @@ dependencies:
   config:
     - filter.format.private_images
   module:
-    - ckeditor
+    - editor_test
 format: private_images
-editor: ckeditor
-settings:
-  toolbar:
-    rows:
-      -
-        -
-          name: Media
-          items:
-            - DrupalImage
-        -
-          name: Tools
-          items:
-            - Source
-  plugins:
-    language:
-      language_list: un
-    stylescombo:
-      styles: ''
+editor: unicorn
 image_upload:
   status: true
   scheme: private
diff --git a/core/modules/editor/tests/modules/src/Plugin/Editor/UnicornEditor.php b/core/modules/editor/tests/modules/src/Plugin/Editor/UnicornEditor.php
index 0317e12adf7..f6a35434a43 100644
--- a/core/modules/editor/tests/modules/src/Plugin/Editor/UnicornEditor.php
+++ b/core/modules/editor/tests/modules/src/Plugin/Editor/UnicornEditor.php
@@ -39,9 +39,25 @@ class UnicornEditor extends EditorBase {
       '#type' => 'checkbox',
       '#default_value' => TRUE,
     ];
+    $form_state->loadInclude('editor', 'admin.inc');
+    $form['image_upload'] = editor_image_upload_settings_form($form_state->get('editor'));
+    $form['image_upload']['#element_validate'][] = [$this, 'validateImageUploadSettings'];
     return $form;
   }
 
+  /**
+   * #element_validate handler for "image_upload" in buildConfigurationForm().
+   *
+   * Moves the text editor's image upload settings into $editor->image_upload.
+   *
+   * @see editor_image_upload_settings_form()
+   */
+  public function validateImageUploadSettings(array $element, FormStateInterface $form_state) {
+    $settings = &$form_state->getValue(['editor', 'settings', 'image_upload']);
+    $form_state->get('editor')->setImageUploadSettings($settings);
+    $form_state->unsetValue(['editor', 'settings', 'image_upload']);
+  }
+
   /**
    * {@inheritdoc}
    */
diff --git a/core/modules/editor/tests/src/Functional/EditorDialogAccessTest.php b/core/modules/editor/tests/src/Functional/EditorDialogAccessTest.php
index 3fcdb18e7e5..f12dca0bbf4 100644
--- a/core/modules/editor/tests/src/Functional/EditorDialogAccessTest.php
+++ b/core/modules/editor/tests/src/Functional/EditorDialogAccessTest.php
@@ -18,7 +18,7 @@ class EditorDialogAccessTest extends BrowserTestBase {
    *
    * @var array
    */
-  protected static $modules = ['editor', 'filter', 'ckeditor'];
+  protected static $modules = ['editor', 'filter', 'editor_test'];
 
   /**
    * {@inheritdoc}
@@ -39,23 +39,8 @@ class EditorDialogAccessTest extends BrowserTestBase {
     // With a text editor but without image upload settings, expect a 200, but
     // there should not be an input[type=file].
     $editor = Editor::create([
-      'editor' => 'ckeditor',
+      'editor' => 'unicorn',
       'format' => 'plain_text',
-      'settings' => [
-        'toolbar' => [
-          'rows' => [
-            [
-              [
-                'name' => 'Media',
-                'items' => [
-                  'DrupalImage',
-                ],
-              ],
-            ],
-          ],
-        ],
-        'plugins' => [],
-      ],
       'image_upload' => [
         'status' => FALSE,
         'scheme' => 'public',
diff --git a/core/modules/editor/tests/src/Functional/EditorPrivateFileReferenceFilterTest.php b/core/modules/editor/tests/src/Functional/EditorPrivateFileReferenceFilterTest.php
index fa93aafd99b..3b073288ef5 100644
--- a/core/modules/editor/tests/src/Functional/EditorPrivateFileReferenceFilterTest.php
+++ b/core/modules/editor/tests/src/Functional/EditorPrivateFileReferenceFilterTest.php
@@ -21,14 +21,12 @@ class EditorPrivateFileReferenceFilterTest extends BrowserTestBase {
    * @var array
    */
   protected static $modules = [
-    // Needed for the config: this is the only module in core that utilizes the
-    // functionality in editor.module to be tested, and depends on that.
-    'ckeditor',
+    'editor_test',
     // Depends on filter.module (indirectly).
     'node',
     // Pulls in the config we're using during testing which create a text format
     // - with the filter_html_image_secure filter DISABLED,
-    // - with the editor set to CKEditor,
+    // - with the editor set to Unicorn editor,
     // - with drupalimage.image_upload.scheme set to 'private',
     // - with drupalimage.image_upload.directory set to ''.
     'editor_private_test',
diff --git a/core/modules/editor/tests/src/FunctionalJavascript/EditorAdminTest.php b/core/modules/editor/tests/src/FunctionalJavascript/EditorAdminTest.php
index c75ede4c5f8..065cb7dc14c 100644
--- a/core/modules/editor/tests/src/FunctionalJavascript/EditorAdminTest.php
+++ b/core/modules/editor/tests/src/FunctionalJavascript/EditorAdminTest.php
@@ -20,7 +20,7 @@ class EditorAdminTest extends WebDriverTestBase {
    * {@inheritdoc}
    */
   protected static $modules = [
-    'ckeditor',
+    'editor_test',
     'ckeditor5',
   ];
 
@@ -53,18 +53,17 @@ class EditorAdminTest extends WebDriverTestBase {
     $page->fillField('name', 'Sulaco');
     // Wait for machine name to be filled in.
     $this->assertNotEmpty($assert_session->waitForText('sulaco'));
-    $page->selectFieldOption('editor[editor]', 'ckeditor');
-    $this->assertNotEmpty($this->assertSession()->waitForElementVisible('css', 'ul.ckeditor-toolbar-group-buttons'));
-    $this->assertNotEmpty($this->assertSession()->waitForElementVisible('css', '#ckeditor-plugin-settings'));
+    $page->selectFieldOption('editor[editor]', 'unicorn');
+    $this->assertNotEmpty($this->assertSession()->waitForField('editor[settings][ponies_too]'));
     $page->pressButton('Save configuration');
 
     // Test that toggling the editor selection off and back on works.
     $this->drupalGet('/admin/config/content/formats/manage/sulaco');
     // Deselect and reselect an editor.
     $page->selectFieldOption('editor[editor]', '');
-    $this->assertNotEmpty($this->assertSession()->waitForElementRemoved('css', 'ul.ckeditor-toolbar-group-buttons'));
-    $page->selectFieldOption('editor[editor]', 'ckeditor');
-    $this->assertNotEmpty($this->assertSession()->waitForElementVisible('css', 'ul.ckeditor-toolbar-group-buttons'));
+    $this->assertNotEmpty($this->assertSession()->waitForElementRemoved('named', ['field', 'editor[settings][ponies_too]']));
+    $page->selectFieldOption('editor[editor]', 'unicorn');
+    $this->assertNotEmpty($this->assertSession()->waitForField('editor[settings][ponies_too]'));
   }
 
   /**
@@ -84,10 +83,11 @@ class EditorAdminTest extends WebDriverTestBase {
     $this->assertNotEmpty($this->assertSession()->waitForElementVisible('css', 'ul.ckeditor5-toolbar-available__buttons'));
 
     $page->selectFieldOption('editor[editor]', '');
-    $assert_session->elementNotExists('css', 'ul.ckeditor-toolbar-group-buttons');
+    $this->assertNotEmpty($this->assertSession()->waitForElementRemoved('css', 'ul.ckeditor5-toolbar-available__buttons'));
+    $this->assertEmpty($this->assertSession()->waitForField('editor[settings][ponies_too]'));
 
-    $page->selectFieldOption('editor[editor]', 'ckeditor');
-    $this->assertNotEmpty($this->assertSession()->waitForElementVisible('css', 'ul.ckeditor-toolbar-group-buttons'));
+    $page->selectFieldOption('editor[editor]', 'unicorn');
+    $this->assertNotEmpty($this->assertSession()->waitForField('editor[settings][ponies_too]'));
   }
 
 }