JavaScript actions that declare node20 now run on Node 24 and the Node 20 opt-out stops working

Symptom

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: ...Node.js 20 actions are deprecated. The following actions are running on Node.js 20 and may not work as expected: ...Older third party actions crash after the runner switch, and self hosted macOS 13.4 or ARM32 runners cannot run them

Cause

GitHub hosted runners switched JavaScript actions to Node 24 by default on June 16, 2026, with ACTIONS_ALLOW_USE_UNSECURE_NODE_VERSION as a temporary escape. Node 20 was removed on September 23, 2026, so that escape no longer applies.

Fix

Upgrade actions to releases that declare node24, test early with FORCE_JAVASCRIPT_ACTIONS_TO_NODE24, and update self hosted runner hosts.

ApplyCopy

env: FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true # then bump: actions/checkout@v5, actions/setup-node@v5, and other node24 releases

Affected

GitHub Actions runners from 2026-06-16 (Node 24 default); Node 20 removed 2026-09-23

Sources

• https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/
• https://github.com/actions/runner/blob/main/src/Runner.Worker/JobExtension.cs
• https://github.com/actions/runner/blob/main/src/Runner.Common/Constants.cs

Last verified 2026-10-15 · Confirmed by 0 builders