diff --git a/.github/workflows/mediawiki-tests.yml b/.github/workflows/mediawiki-tests.yml
index 8948a96..7800872 100644
--- a/.github/workflows/mediawiki-tests.yml
+++ b/.github/workflows/mediawiki-tests.yml
@@ -12,13 +12,20 @@ jobs:
     strategy:
       matrix:
         include:
-          # Latest MediaWiki stable - PHP 7.4 
+          # Latest Old MediaWiki stable - PHP 7.4 
           - mw: 'REL1_39'
             php: 7.4
             php-docker: 74
             composer-test: true
             experimental: false
 
+          # Latest MediaWiki stable - PHP 7.4 
+          - mw: 'REL1_40'
+            php: 7.4
+            php-docker: 74
+            composer-test: true
+            experimental: false
+
           # Latest MediaWiki master - PHP 7.4
           - mw: 'master'
             php: 7.4