diff --git a/.github/workflows/CI.yml b/.github/workflows/CI.yml
index e48a8c1..ccaa22e 100644
--- a/.github/workflows/CI.yml
+++ b/.github/workflows/CI.yml
@@ -47,6 +47,8 @@ jobs:
       - run: sudo apt-get update && sudo apt-get install -y xorg-dev mesa-utils xvfb libgl1 freeglut3-dev libxrandr-dev libxinerama-dev libxcursor-dev libxi-dev libxext-dev xsettingsd x11-xserver-utils
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-runtest@v1
+        with:
+          prefix: xvfb-run -s '-screen 0 1024x768x24'
       - uses: julia-actions/julia-processcoverage@v1
       - uses: codecov/codecov-action@v1
         with: