ENH Improve type safety to support refactored template layer

_config.php

@@ -1,5 +1,10 @@
 <?php
 
+use SilverStripe\Admin\CMSMenu;
+use SilverStripe\CMS\Controllers\CMSMain;
+use SilverStripe\CMS\Controllers\CMSPageAddController;
+use SilverStripe\CMS\Controllers\CMSPageEditController;
+use SilverStripe\CMS\Controllers\CMSPageSettingsController;
 use SilverStripe\CMS\Model\SiteTree;
 use SilverStripe\Core\Manifest\ModuleLoader;
 use SilverStripe\Forms\HTMLEditor\TinyMCEConfig;
@@ -26,3 +31,8 @@ ShortcodeParser::get('default')->register(
     'sitetree_link',
     [SiteTree::class, 'link_shortcode_handler']
 );
+
+CMSMenu::remove_menu_class(CMSMain::class);
+CMSMenu::remove_menu_class(CMSPageEditController::class);
+CMSMenu::remove_menu_class(CMSPageSettingsController::class);
+CMSMenu::remove_menu_class(CMSPageAddController::class);

code/Controllers/CMSPageAddController.php

@@ -32,8 +32,6 @@ class CMSPageAddController extends CMSPageEditController
     private static $menu_title = 'Add page';
     private static $required_permission_codes = 'CMS_ACCESS_CMSMain';
 
-    private static $ignore_menuitem = true;
-
     private static $allowed_actions = [
         'AddForm',
         'doAdd',

code/Controllers/CMSPageEditController.php

@@ -28,13 +28,11 @@ class CMSPageEditController extends CMSMain
 
     private static $required_permission_codes = 'CMS_ACCESS_CMSMain';
 
-    private static $ignore_menuitem = true;
-
     private static $allowed_actions = [
         'AddToCampaignForm',
     ];
 
-    public function getClientConfig(): array
+    public function getClientConfig()
     {
         return ArrayLib::array_merge_recursive(parent::getClientConfig(), [
             'form' => [

code/Controllers/CMSPageSettingsController.php

@@ -15,8 +15,6 @@ class CMSPageSettingsController extends CMSMain
 
     private static $required_permission_codes = 'CMS_ACCESS_CMSMain';
 
-    private static $ignore_menuitem = true;
-
     public function getEditForm($id = null, $fields = null)
     {
         $record = $this->getRecord($id ?: $this->currentPageID());