ESLint: Rename root eslint.config.cjs to eslint.config.mjs

[manzoorwanijk]

What?

Follow up to #77215.

Renames the root eslint.config.cjs to eslint.config.mjs and replaces the dynamic import() re-export with a static export { default }.

Why?

#77215 kept the root file as CommonJS only so git would detect the rename of the original eslint.config.mjs into tools/eslint/config.mjs. That history is now recorded, so the root file can go back to ESM and drop the promise-returning import() wrapper.

How?

git mv to .mjs plus a one-line static re-export in eslint.config.mjs. Docs referencing the old filename are updated.

Testing Instructions

1. npm run lint:js passes.
2. Open a .js file in VS Code and confirm ESLint squiggles still appear.
3. Introduce var x = 1; in a package file and confirm it is reported.

Testing Instructions for Keyboard

N/A, no UI changes.

Use of AI Tools

Authored with assistance from Claude Code (Claude Opus 5). All changes were reviewed and verified manually.

[github-actions]

The following accounts have interacted with this PR and/or linked issues. I will continue to update these lists as activity occurs. You can also manually ask me to refresh this list by adding the props-bot label.

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Co-authored-by: manzoorwanijk <manzoorwanijk@git.wordpress.org>
Co-authored-by: Mamaduka <mamaduka@git.wordpress.org>

To understand the WordPress project's expectations around crediting contributors, please review the Contributor Attribution page in the Core Handbook.

[github-actions]

Size Change: 0 B

Total Size: 7.71 MB

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[github-actions]

Flaky tests detected in 8ff6837.
Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/31569897293
📝 Reported tests:

does not dirty related template parts or navigation menus when rendered in the post editor in /test/e2e/specs/editor/blocks/navigation-passive-rendering.spec.js, passed after 1 failed attempt.

Error: apiRequestContext.fetch: socket hang up
Call log:
  - → GET http://localhost:8889/wp-json/wp/v2/templates
    - user-agent: Playwright/1.62.1 (x64; ubuntu 24.04) node/20.20 CI/1
    - accept: */*
    - accept-encoding: gzip,deflate,br
    - X-WP-Nonce: 01e8716472
    - cookie: wordpress_test_cookie=WP%20Cookie%20check; wordpress_logged_in_23778236db82f19306f247e20a353a99=admin%7C1786688976%7CWWacUZYMFW9RSoM6oy4E84PjnmHxNy7vzdErsGworzo%7C3282faac4e5de507aa2bf902d213c9f8179feb90a8d9a0bf762ac2963f447e55; wp-settings-time-1=1786516266

    at RequestUtils.rest (/home/runner/work/gutenberg/gutenberg/packages/e2e-test-utils-playwright/src/request-utils/rest.ts:112:39)
    at RequestUtils.deleteAllTemplates (/home/runner/work/gutenberg/gutenberg/packages/e2e-test-utils-playwright/src/request-utils/templates.ts:35:31)
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/blocks/navigation-passive-rendering.spec.js:48:17

should show the admin bar in /test/e2e/specs/editor/various/fullscreen-mode.spec.js, passed after 1 failed attempt.

Error: apiRequestContext.get: socket hang up
Call log:
  - → GET http://localhost:8889/wp-admin/themes.php?action=activate&stylesheet=emptytheme&_wpnonce=bdc64357a6
    - user-agent: Playwright/1.62.1 (x64; ubuntu 24.04) node/20.20 CI/1
    - accept: */*
    - accept-encoding: gzip,deflate,br
    - cookie: wordpress_test_cookie=WP%20Cookie%20check; wordpress_23778236db82f19306f247e20a353a99=admin%7C1786688996%7C9z7BcqNteVziVQM9sSgzNs7ZUC6fBHHIMIwhLsRaRoS%7Ce3e630b3b30b5d3b08a053a09198a2794606248e1deedfd37d7badc1d4892080; wordpress_logged_in_23778236db82f19306f247e20a353a99=admin%7C1786688996%7C9z7BcqNteVziVQM9sSgzNs7ZUC6fBHHIMIwhLsRaRoS%7C98feca5457c70cb316c6e41fc915b0e1afe306267adb7dcd3521ccf0b6714679; wp-settings-time-1=1786516540; wp-settings-1=editor%3Dtinymce
  - ← 302 Found
    - date: Wed, 12 Aug 2026 06:37:58 GMT
    - server: Apache/2.4.68 (Debian)
    - x-powered-by: PHP/8.3.33
    - expires: Wed, 11 Jan 1984 05:00:00 GMT
    - cache-control: no-cache, must-revalidate, max-age=0, private
    - referrer-policy: strict-origin-when-cross-origin
    - x-frame-options: SAMEORIGIN
    - content-security-policy: frame-ancestors 'self';
    - x-redirect-by: WordPress
    - location: http://localhost:8889/wp-admin/themes.php?activated=true
    - server-timing: wpTotal;dur=26.36, wpMemoryUsage;dur=4805104, wpDbQueries;dur=43
    - content-length: 0
    - keep-alive: timeout=5, max=93
    - connection: Keep-Alive
    - content-type: text/html; charset=UTF-8
  - → GET http://localhost:8889/wp-admin/themes.php?activated=true
    - user-agent: Playwright/1.62.1 (x64; ubuntu 24.04) node/20.20 CI/1
    - accept: */*
    - accept-encoding: gzip,deflate,br
    - host: localhost:8889
    - cookie: wordpress_test_cookie=WP%20Cookie%20check; wordpress_23778236db82f19306f247e20a353a99=admin%7C1786688996%7C9z7BcqNteVziVQM9sSgzNs7ZUC6fBHHIMIwhLsRaRoS%7Ce3e630b3b30b5d3b08a053a09198a2794606248e1deedfd37d7badc1d4892080; wordpress_logged_in_23778236db82f19306f247e20a353a99=admin%7C1786688996%7C9z7BcqNteVziVQM9sSgzNs7ZUC6fBHHIMIwhLsRaRoS%7C98feca5457c70cb316c6e41fc915b0e1afe306267adb7dcd3521ccf0b6714679; wp-settings-time-1=1786516540; wp-settings-1=editor%3Dtinymce

    at RequestUtils.activateTheme (/home/runner/work/gutenberg/gutenberg/packages/e2e-test-utils-playwright/src/request-utils/themes.ts:45:32)
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/fullscreen-mode.spec.js:87:4