By default, a React application created using Create React App starts the default browser when launching the application. This can be annoying if you are using a different browser from your default one for development. Here’s how to make react-scripts start the application with the browser of your choice or without a browser.

Start with a different browser

In your package.json file under the scripts section for start add the parameter BROWSER=InsertNameOfBrowserHere before the react-scripts start command.

"scripts": {
    "start": "BROWSER=firefox react-scripts start",
}

Start without a browser

To launch your application without starting a browser, place NONE instead of the filename of the browser as the value for the BROWSER parameter.

"scripts": {
    "start": "BROWSER=NONE react-scripts start",
}