Reference for JS magic comments

[Josh-Cena]

As tracked by the Google team.

• https://chromestatus.com/feature/5100466238652416
• https://issuetracker.google.com/issues/508498716

[github-actions]

Preview URLs (1 page)

• /en-US/docs/Web/JavaScript/Reference/Magic_comments

External URLs (18)

URL: /en-US/docs/Web/JavaScript/Reference/Magic_comments
Title: Magic comments

• https://archives.ecma-international.org/2007/misc/jscriptconditionalcompilation2.pdf (1 time) (Note! This may be a new URL 👀)
• https://babeljs.io/docs/babel-plugin-transform-react-jsx/ (1 time) (Note! This may be a new URL 👀)
• https://developer.chrome.com/docs/devtools/javascript/source-maps (1 time) (Note! This may be a new URL 👀)
• https://esbuild.github.io/api/ (2 times) (Note! This may be a new URL 👀)
• https://eslint.org/docs/latest/use/configure/rules (1 time) (Note! This may be a new URL 👀)
• https://flow.org/en/docs/getting-started/ (1 time) (Note! This may be a new URL 👀)
• https://flow.org/en/docs/types/comments/ (1 time) (Note! This may be a new URL 👀)
• https://prettier.io/docs/ignore (1 time) (Note! This may be a new URL 👀)
• https://react.dev/reference/rsc/use-server (1 time) (Note! This may be a new URL 👀)
• https://rollupjs.org/configuration-options/ (1 time) (Note! This may be a new URL 👀)
• https://tc39.es/ecma426/ (2 times) (Note! This may be a new URL 👀)
• https://terser.org/docs/miscellaneous/ (2 times) (Note! This may be a new URL 👀)
• https://v8.dev/blog/explicit-compile-hints (1 time) (Note! This may be a new URL 👀)
• https://web.archive.org/web/20120814122523/http://blog.getfirebug.com/2009/08/11/give-your-eval-a-name-with-sourceurl/ (1 time) (Note! This may be a new URL 👀)
• https://wicg.github.io/explicit-javascript-compile-hints-file-based/ (1 time) (Note! This may be a new URL 👀)
• https://www.typescriptlang.org/docs/handbook/jsdoc-supported-types.html (1 time) (Note! This may be a new URL 👀)
• https://www.typescriptlang.org/docs/handbook/release-notes/typescript-2-3.html (1 time) (Note! This may be a new URL 👀)
• https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-9.html (1 time) (Note! This may be a new URL 👀)

(comment last updated: 2026-09-29 15:45:39)

[chrisdavidmills]

Nice work, @Josh-Cena; I found this interesting and informative to read. I've left you a few nitpicks to check over. I'll also ask Marja to give this a tech review.

[Josh-Cena]

Wow, looks like I wrote an embarrassing amount of typos. Definitely not sleeping well.

[chrisdavidmills]

This looks good to me from an editorial standpoint; approving.

I'll hold off on merging to see if we can get a tech review on this. Maybe you could merge it in a few days if you don't hear anything?

[Josh-Cena]

Alright 👍 Have you pinged anyone to do tech review?

[chrisdavidmills]

Alright 👍 Have you pinged anyone to do tech review?

Yes, I emailed @marjakh to ask if she'd have a look. I guess I've pinged her here now too ;-)

[Josh-Cena]

OK! I'll hold this until Friday.

[marjakh]

I only looked at the parts about compile hints; comments inline

[Josh-Cena]

I'll merge in the next 24 hours if everything looks good—thanks!

[Josh-Cena]

Merging. Thanks both!