diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index af13632..a6f5724 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -63,7 +63,7 @@ jobs:
     steps:
       - name: Notify Slack
         if: env.SLACK_WEBHOOK_URL != ''
-        uses: slackapi/slack-github-action@v3
+        uses: slackapi/slack-github-action@v4
         with:
           payload: |
             {"text":"CI failed in ${{ github.repository }}\n${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"}
diff --git a/.github/workflows/promote-prod.yml b/.github/workflows/promote-prod.yml
index 2aa46d0..6d7cab2 100644
--- a/.github/workflows/promote-prod.yml
+++ b/.github/workflows/promote-prod.yml
@@ -322,7 +322,7 @@ jobs:
       - name: Notify Slack
         if: env.SLACK_WEBHOOK_URL != ''
         continue-on-error: true
-        uses: slackapi/slack-github-action@v3
+        uses: slackapi/slack-github-action@v4
         with:
           webhook: ${{ secrets.SLACK_WEBHOOK_URL }}
           webhook-type: incoming-webhook
@@ -403,7 +403,7 @@ jobs:
       - name: Notify Slack
         if: env.SLACK_WEBHOOK_URL != ''
         continue-on-error: true   # a Slack hiccup must never red an already-published release
-        uses: slackapi/slack-github-action@v3
+        uses: slackapi/slack-github-action@v4
         with:
           webhook: ${{ secrets.SLACK_WEBHOOK_URL }}
           webhook-type: incoming-webhook
@@ -428,7 +428,7 @@ jobs:
     steps:
       - name: Notify Slack
         if: env.SLACK_WEBHOOK_URL != ''
-        uses: slackapi/slack-github-action@v3
+        uses: slackapi/slack-github-action@v4
         with:
           # v2+ requires the URL via the `webhook` input + an explicit `webhook-type`.
           # SLACK_WEBHOOK_URL is a classic Incoming Webhook -> incoming-webhook.
diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index 1bfcf38..9d6f093 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -152,7 +152,7 @@ jobs:
     steps:
       - name: Notify Slack
         if: env.SLACK_WEBHOOK_URL != ''
-        uses: slackapi/slack-github-action@v3
+        uses: slackapi/slack-github-action@v4
         with:
           # v2+ requires the URL via the `webhook` input + an explicit `webhook-type`
           # (the v1 env-only style fails with "Missing input! The webhook type must be