diff --git a/_config/config.yml b/_config/config.yml
index a3f5abef..06facb6e 100644
--- a/_config/config.yml
+++ b/_config/config.yml
@@ -2,8 +2,12 @@
 Name: campaignadmin
 ---
 SilverStripe\Admin\LeftAndMain:
-  extensions:
-    - SilverStripe\CampaignAdmin\CampaignAdminExtension
+  extra_requirements_i18n:
+    - 'silverstripe/campaign-admin: client/lang'
+  extra_requirements_javascript:
+    - 'silverstripe/campaign-admin: client/dist/js/bundle.js'
+  extra_requirements_css:
+    - 'silverstripe/campaign-admin: client/dist/styles/bundle.css'
 
 SilverStripe\CMS\Model\SiteTree:
   extensions:
diff --git a/src/CampaignAdminExtension.php b/src/CampaignAdminExtension.php
deleted file mode 100644
index 4d2ea602..00000000
--- a/src/CampaignAdminExtension.php
+++ /dev/null
@@ -1,30 +0,0 @@
-<?php
-
-namespace SilverStripe\CampaignAdmin;
-
-use SilverStripe\Admin\LeftAndMain;
-use SilverStripe\Core\Extension;
-use SilverStripe\Dev\Deprecation;
-use SilverStripe\View\Requirements;
-
-/**
- * @extends Extension<LeftAndMain>
- * @deprecated 5.3.0 Will be replaced with YAML configuration
- */
-class CampaignAdminExtension extends Extension
-{
-    public function __construct()
-    {
-        Deprecation::withNoReplacement(
-            fn () => Deprecation::notice('5.3.0', 'Will be replaced with YAML configuration', Deprecation::SCOPE_CLASS)
-        );
-        parent::__construct();
-    }
-
-    public function init()
-    {
-        Requirements::add_i18n_javascript('silverstripe/campaign-admin: client/lang', false);
-        Requirements::javascript('silverstripe/campaign-admin: client/dist/js/bundle.js');
-        Requirements::css('silverstripe/campaign-admin: client/dist/styles/bundle.css');
-    }
-}