diff --git a/.gitea/workflows/ci.yml b/.gitea/workflows/ci.yml
index 9b0002d..edb2cf7 100644
--- a/.gitea/workflows/ci.yml
+++ b/.gitea/workflows/ci.yml
@@ -64,6 +64,10 @@ jobs:
       IMAGE: ${{ vars.REGISTRY }}/${{ github.repository }}
       TAG: ${{ github.ref_name }}
       PACKAGE_TOKEN: ${{ secrets.PACKAGE_TOKEN }}
+      # The forge's public address, for the "View source code" link. Not
+      # GITHUB_SERVER_URL: on this runner that is Gitea's internal address,
+      # which no visitor can reach.
+      PUBLIC_URL: https://git.coffeylabs.org
     steps:
       - uses: coffey-labs/actions/checkout@fab0c4d45e0162963965f1555df27b7bed5e20ec
         with:
@@ -89,7 +93,7 @@ jobs:
           docker build \
             --build-arg MASTODON_VERSION_METADATA="$METADATA" \
             --build-arg SOURCE_COMMIT="$GITHUB_SHA" \
-            --build-arg SOURCE_BASE_URL="$GITHUB_SERVER_URL/$GITHUB_REPOSITORY" \
+            --build-arg SOURCE_BASE_URL="$PUBLIC_URL/$GITHUB_REPOSITORY" \
             --build-arg SOURCE_TAG="$TAG" \
             --tag "$IMAGE:$TAG" .
           docker push "$IMAGE:$TAG"