diff --git a/.github/workflows/gh-pages.yml b/.github/workflows/gh-pages.yml
index eb1a8ed2..8dc6b3de 100644
--- a/.github/workflows/gh-pages.yml
+++ b/.github/workflows/gh-pages.yml
@@ -23,6 +23,9 @@ jobs:
           submodules: recursive
           fetch-depth: 0
 
+      - name: Checkout submodules
+        run: git submodule update --init --recursive
+
       - name: Set up Python
         uses: actions/setup-python@v2.2.1
         with: