diff --git a/.github/workflows/pynblint.yml b/.github/workflows/pynblint.yml
index d62dd3b..aaeeae6 100644
--- a/.github/workflows/pynblint.yml
+++ b/.github/workflows/pynblint.yml
@@ -19,5 +19,7 @@ jobs:
       # Install pynblint
       - name: Install pynblint
         run: sudo pip install pynblint
+      - name: Install lxml[html_clean]
+        run: sudo pip install lxml[html_clean]
       - name: Run pynblint
         run: pynblint $GITHUB_WORKSPACE