Issue #3238915: Refactor (if feasible) uses of the jQuery ready function to use VanillaJS

core/modules/ckeditor5/src/Plugin/CKEditor4To5Upgrade/Contrib.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\ckeditor5\Plugin\CKEditor4To5Upgrade;
+
+use Drupal\ckeditor5\HTMLRestrictions;
+use Drupal\ckeditor5\Plugin\CKEditor4To5UpgradePluginInterface;
+use Drupal\Core\Plugin\PluginBase;
+use Drupal\filter\FilterFormatInterface;
+
+/**
+ * Provides the CKEditor 4 to 5 upgrade path for contrib plugins now in core.
+ *
+ * @CKEditor4To5Upgrade(
+ *   id = "contrib",
+ *   cke4_buttons = {
+ *     "Code"
+ *   },
+ *   cke4_plugin_settings = {
+ *   },
+ *   cke5_plugin_elements_subset_configuration = {
+ *   }
+ * )
+ *
+ * @internal
+ *   Plugin classes are internal.
+ */
+class Contrib extends PluginBase implements CKEditor4To5UpgradePluginInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function mapCKEditor4ToolbarButtonToCKEditor5ToolbarItem(string $cke4_button, HTMLRestrictions $text_format_html_restrictions): ?array {
+    switch ($cke4_button) {
+      // @see https://www.drupal.org/project/codetag
+      case 'Code':
+        return ['code'];
+
+      default:
+        throw new \OutOfBoundsException();
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function mapCKEditor4SettingsToCKEditor5Configuration(string $cke4_plugin_id, array $cke4_plugin_settings): ?array {
+    throw new \OutOfBoundsException();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function computeCKEditor5PluginSubsetConfiguration(string $cke5_plugin_id, FilterFormatInterface $text_format): ?array {
+    throw new \OutOfBoundsException();
+  }
+
+}