diff --git a/website/scripts/vercel-ignore.sh b/website/scripts/vercel-ignore.sh
index b200e414f812..6423083bf11f 100755
--- a/website/scripts/vercel-ignore.sh
+++ b/website/scripts/vercel-ignore.sh
@@ -34,6 +34,12 @@ skip() {
 
 cd "$(git rev-parse --show-toplevel)" || build "cannot find repo root"
 
+# Vercel's clone has no `origin` remote, so every fetch below would fail. Add
+# one for the (public) repo; the clone is thrown away after the build.
+git remote get-url origin >/dev/null 2>&1 ||
+  { [ -n "${VERCEL_GIT_REPO_OWNER:-}" ] && [ -n "${VERCEL_GIT_REPO_SLUG:-}" ] &&
+    git remote add origin "https://github.com/$VERCEL_GIT_REPO_OWNER/$VERCEL_GIT_REPO_SLUG.git"; }
+
 # Builds if site paths changed between $1 and $2 (or the diff fails); else skips.
 decide() {
   local files
diff --git a/website/scripts/vercel-ignore.test.sh b/website/scripts/vercel-ignore.test.sh
index c77218f6a02c..eabf8cc6f007 100755
--- a/website/scripts/vercel-ignore.test.sh
+++ b/website/scripts/vercel-ignore.test.sh
@@ -232,10 +232,16 @@ for branch in far-pkg far-site; do
   clone="$(mktemp -d)"
   git clone -q --depth=10 --branch "$branch" "file://$origin_repo" "$clone"
   git -C "$clone" branch -f master HEAD
+  # Like Vercel's clone: no `origin` remote, so the script must fetch by URL.
+  git -C "$clone" remote remove origin
   repo="$clone"
   want=skip
   [ "$branch" = far-site ] && want=build
-  expect "$want" "shallow clone, fork far behind master ($branch)" "$branch"
+  GIT_CONFIG_COUNT=3 \
+    GIT_CONFIG_KEY_2="url.file://$origin_repo.insteadOf" \
+    GIT_CONFIG_VALUE_2=https://github.com/test-owner/test-repo.git \
+    VERCEL_GIT_REPO_OWNER=test-owner VERCEL_GIT_REPO_SLUG=test-repo \
+    expect "$want" "shallow clone without origin, fork far behind master ($branch)" "$branch"
   repo="$origin_repo"
   rm -rf "$clone"
 done