diff --git a/_config/extensions.yml b/_config/extensions.yml
index 8d4b0a57..36ece43c 100644
--- a/_config/extensions.yml
+++ b/_config/extensions.yml
@@ -51,10 +51,6 @@ SilverStripe\CMS\Controllers\CMSMain:
     - SilverStripe\Subsites\Extensions\HintsCacheKeyExtension
     - SilverStripe\Subsites\Extensions\SubsiteMenuExtension
 
-SilverStripe\CMS\Controllers\CMSPagesController:
-  extensions:
-    - SilverStripe\Subsites\Extensions\SubsiteMenuExtension
-
 SilverStripe\Subsites\Admin\SubsiteAdmin:
   extensions:
     - SilverStripe\Subsites\Extensions\SubsiteMenuExtension
diff --git a/lang/en.yml b/lang/en.yml
index 418d8918..461461e7 100644
--- a/lang/en.yml
+++ b/lang/en.yml
@@ -81,6 +81,7 @@ en:
     db_Protocol: Protocol
     has_one_Subsite: Subsite
   SilverStripe\Subsites\Pages\SubsitesVirtualPage:
+    CLASS_DESCRIPTION: 'Displays the content of a page on another subsite'
     DESCRIPTION: 'Displays the content of a page on another subsite'
     OverrideNote: 'Overrides inherited value from the source'
     PLURALNAME: 'Subsites Virtual Pages'
diff --git a/src/Extensions/LeftAndMainSubsites.php b/src/Extensions/LeftAndMainSubsites.php
index c6a1b74a..8e2b8607 100644
--- a/src/Extensions/LeftAndMainSubsites.php
+++ b/src/Extensions/LeftAndMainSubsites.php
@@ -6,7 +6,7 @@
 use SilverStripe\Admin\CMSMenu;
 use SilverStripe\Admin\CMSProfileController;
 use SilverStripe\Admin\LeftAndMain;
-use SilverStripe\CMS\Controllers\CMSPagesController;
+use SilverStripe\CMS\Controllers\CMSMain;
 use SilverStripe\CMS\Model\SiteTree;
 use SilverStripe\CMS\Controllers\CMSPageEditController;
 use SilverStripe\Control\Controller;
@@ -280,7 +280,7 @@ protected function onBeforeInit()
                 // sessionNamespace() is protected - see for info
                 $override = $this->owner->config()->get('session_namespace');
                 $sessionNamespace = $override ? $override : get_class($this->owner);
-                $session->clear($sessionNamespace . '.currentPage');
+                $session->clear($sessionNamespace . '.currentRecord');
             }
 
             // Context: Subsite ID has already been set to the state via InitStateMiddleware
@@ -293,13 +293,13 @@ protected function onBeforeInit()
             $currentController = Controller::curr();
             if ($currentController instanceof CMSPageEditController) {
                 /** @var SiteTree $page */
-                $page = $currentController->currentPage();
+                $page = $currentController->currentRecord();
 
                 // If the page exists but doesn't belong to the requested subsite, redirect to admin/pages which
                 // will show a list of the requested subsite's pages
                 $currentSubsiteId = $request->getVar('SubsiteID');
                 if ($page && (int) $page->SubsiteID !== (int) $currentSubsiteId) {
-                    return $this->owner->redirect(CMSPagesController::singleton()->Link());
+                    return $this->owner->redirect(CMSMain::singleton()->Link());
                 }
 
                 // Page does belong to the current subsite, so remove the query string parameter and refresh the page
@@ -314,7 +314,7 @@ protected function onBeforeInit()
 
         // Automatically redirect the session to appropriate subsite when requesting a record.
         // This is needed to properly initialise the session in situations where someone opens the CMS via a link.
-        $record = $this->owner->currentPage();
+        $record = $this->owner->currentRecord();
         if ($record
             && isset($record->SubsiteID, $this->owner->urlParams['ID'])
             && is_numeric($record->SubsiteID)
@@ -379,7 +379,7 @@ protected function onBeforeInit()
         return;
     }
 
-    protected function augmentNewSiteTreeItem(&$item)
+    protected function updateNewItem(&$item)
     {
         $request = Controller::curr()->getRequest();
         $item->SubsiteID = $request->postVar('SubsiteID') ?: SubsiteState::singleton()->getSubsiteId();
diff --git a/src/Model/Subsite.php b/src/Model/Subsite.php
index 8ac132fe..a185a110 100644
--- a/src/Model/Subsite.php
+++ b/src/Model/Subsite.php
@@ -728,7 +728,8 @@ public function getPageTypeMap()
     {
         $pageTypeMap = [];
 
-        $pageTypes = SiteTree::page_type_classes();
+        $pageTypes = ClassInfo::getValidSubClasses(SiteTree::class);
+        SiteTree::singleton()->updateAllowedSubClasses($pageTypes);
         foreach ($pageTypes as $pageType) {
             $pageTypeMap[$pageType] = singleton($pageType)->i18n_singular_name();
         }
diff --git a/src/Pages/SubsitesVirtualPage.php b/src/Pages/SubsitesVirtualPage.php
index 8f9ff22a..a9198198 100644
--- a/src/Pages/SubsitesVirtualPage.php
+++ b/src/Pages/SubsitesVirtualPage.php
@@ -21,7 +21,7 @@ class SubsitesVirtualPage extends VirtualPage
 {
     private static $table_name = 'SubsitesVirtualPage';
 
-    private static $description = 'Displays the content of a page on another subsite';
+    private static $class_description = 'Displays the content of a page on another subsite';
 
     private static $non_virtual_fields = [
         'SubsiteID'
diff --git a/tests/php/SiteTreeSubsitesTest.php b/tests/php/SiteTreeSubsitesTest.php
index adb65115..b0adca56 100644
--- a/tests/php/SiteTreeSubsitesTest.php
+++ b/tests/php/SiteTreeSubsitesTest.php
@@ -287,7 +287,7 @@ public function testPageTypesBlacklistInCMSMain()
 
         Subsite::changeSubsite($s1);
         $cmsmain = CMSMain::create();
-        $hints = json_decode($cmsmain->SiteTreeHints() ?? '', true);
+        $hints = json_decode($cmsmain->TreeHints() ?? '', true);
         $classes = $hints['Root']['disallowedChildren'];
         $this->assertContains(ErrorPage::class, $classes);
         $this->assertContains(TestClassA::class, $classes);
@@ -298,7 +298,7 @@ public function testPageTypesBlacklistInCMSMain()
         if ($cmsmain->hasMethod('getHintsCache')) {
             $cmsmain->getHintsCache()->clear();
         }
-        $hints = json_decode($cmsmain->SiteTreeHints() ?? '', true);
+        $hints = json_decode($cmsmain->TreeHints() ?? '', true);
 
         $classes = $hints['Root']['disallowedChildren'];
         $this->assertNotContains(ErrorPage::class, $classes);