diff --git a/.github/workflows/documentation-build.yml b/.github/workflows/documentation-build.yml
index 396ccd62b..0e4e37e64 100644
--- a/.github/workflows/documentation-build.yml
+++ b/.github/workflows/documentation-build.yml
@@ -22,6 +22,8 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@v6
+        with:
+          submodules: true
 
       - name: Install Graphviz
         run: |