diff --git a/.github/workflows/external.yml b/.github/workflows/external.yml
index 4f87cb1a..a8d18a33 100644
--- a/.github/workflows/external.yml
+++ b/.github/workflows/external.yml
@@ -74,7 +74,7 @@ jobs:
     - name: Install Xvfb
       run: |
         sudo apt-get update
-        sudo apt-get install -y xvfb
+        sudo apt-get install -y xvfb libc++1
 
     - name: Start Xvfb
       run: Xvfb :99 -screen 0 1024x768x24 &