Xvfb test

.github/workflows/CI.yml

@@ -7,8 +7,6 @@ on:
   pull_request:
   workflow_dispatch:
 concurrency:
-  # Skip intermediate builds: always.
-  # Cancel intermediate builds: only if it is a pull request build.
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: ${{ startsWith(github.ref, 'refs/pull/') }}
 jobs:
@@ -31,6 +29,9 @@ jobs:
         with:
           version: ${{ matrix.version }}
           arch: ${{ matrix.arch }}
+      # This step uses a GitHub Action and does not require a `run` command
+      - name: Setup Xvfb
+        uses: coactions/[email protected]
       - uses: julia-actions/cache@v1
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-runtest@v1