diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 95f30d6..9aa5cba 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -57,12 +57,12 @@ jobs:
         # Recent versions of Github's checkout action do not run on older Ubuntu versions because they use a too recent
         # Node.js version. Thus, we have to checkout the code manually.
         run: |
-          echo "Repo: $(awk -v a=${{github.event.pull_request.head.repo.clone_url}} -v b=${{github.repositoryUrl}} 'BEGIN { if (a == "")  { print b } else { print a } }')"
+          echo "Repo: $(awk -v a=${{github.event.pull_request.head.repo.clone_url}} -v b="${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}" 'BEGIN { if (a == "")  { print b } else { print a } }')"
           echo "Branch: ${GITHUB_HEAD_REF}"
           apt-get update
           apt-get install -y git
           git config --global --add safe.directory '*'
-          git clone $(awk -v a=${{github.event.pull_request.head.repo.clone_url}} -v b=${{github.repositoryUrl}} 'BEGIN { if (a == "")  { print b } else { print a } }') .
+          git clone $(awk -v a=${{github.event.pull_request.head.repo.clone_url}} -v b="${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}" 'BEGIN { if (a == "")  { print b } else { print a } }') .
           git checkout $GITHUB_HEAD_REF
 
       - name: Setup (macOS)