diff --git a/app/assets/javascripts/discourse/tests/fixtures/site-settings.js b/app/assets/javascripts/discourse/tests/fixtures/site-settings.js
index 75f66c1cec..0a37ea9ab4 100644
--- a/app/assets/javascripts/discourse/tests/fixtures/site-settings.js
+++ b/app/assets/javascripts/discourse/tests/fixtures/site-settings.js
@@ -78,8 +78,5 @@ export default {
         value: "",
       },
     ],
-    diags: {
-      last_message_processed: null,
-    },
   },
 };
diff --git a/app/controllers/admin/site_settings_controller.rb b/app/controllers/admin/site_settings_controller.rb
index ad28e93af4..18ae3d3165 100644
--- a/app/controllers/admin/site_settings_controller.rb
+++ b/app/controllers/admin/site_settings_controller.rb
@@ -6,7 +6,7 @@ class Admin::SiteSettingsController < Admin::AdminController
   end
 
   def index
-    render_json_dump(site_settings: SiteSetting.all_settings, diags: SiteSetting.diags)
+    render_json_dump(site_settings: SiteSetting.all_settings)
   end
 
   def update
diff --git a/lib/site_setting_extension.rb b/lib/site_setting_extension.rb
index d89408a63d..71c0eba09a 100644
--- a/lib/site_setting_extension.rb
+++ b/lib/site_setting_extension.rb
@@ -323,7 +323,6 @@ module SiteSettingExtension
 
   def process_message(message)
     begin
-      @last_message_processed = message.global_id
       MessageBus.on_connect.call(message.site_id)
       refresh!
     ensure
@@ -331,10 +330,6 @@ module SiteSettingExtension
     end
   end
 
-  def diags
-    { last_message_processed: @last_message_processed }
-  end
-
   def process_id
     @process_id ||= SecureRandom.uuid
   end