diff --git a/.github/workflows/formats.yml b/.github/workflows/formats.yml
index f3598b3b..bbdd5771 100644
--- a/.github/workflows/formats.yml
+++ b/.github/workflows/formats.yml
@@ -30,7 +30,7 @@ jobs:
       uses: shivammathur/setup-php@v2
       with:
         php-version: ${{ matrix.php }}
-        extensions: mbstring, zip
+        extensions: dom, mbstring, zip
         tools: prestissimo
         coverage: pcov
 
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 10188221..8c600d9d 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -29,7 +29,7 @@ jobs:
       uses: shivammathur/setup-php@v2
       with:
         php-version: ${{ matrix.php }}
-        extensions: mbstring, zip
+        extensions: dom, mbstring, zip
         coverage: none
 
     - name: Install Composer dependencies