reactStrictMode
Good to know
Since Next.js 13.5.1, Strict Mode is true by default with app router, so the above configuration is only necessary for pages. You can still disable Strict Mode by setting reactStrictMode: false.
Suggested
We strongly suggest you enable Strict Mode in your Next.js application to better prepare your application for the future of React.
React's Strict Mode is a development mode only feature for highlighting potential problems in an application. It helps to identify unsafe lifecycles, legacy API usage, and a number of other features.
The Next.js runtime is Strict Mode-compliant. To opt-in to Strict Mode, configure the following option in your next.config.js:
module.exports = {
reactStrictMode: true,
}If you or your team are not ready to use Strict Mode in your entire application, that's OK! You can incrementally migrate on a page-by-page basis using <React.StrictMode>.