[StackOverflow/reactjs] React app not working in Safari. Working fine on Chrome and FireFox but giving black layout for safari

### ROOT CAUSE The issue arises because Safari's JavaScript engine (JavaScriptCore) has stricter ES6 compliance and may not support certain modern JavaScript features or CSS properties used in the React app. The black layout likely stems from a JavaScript error preventing component rendering or a CSS property (e.g., Flexbox) not being supported in older Safari versions. ### CODE FIX 1. **Add Babel Preset for ES6 Compatibility** Ensure `@babel/preset-env` is configured with Safari targets in `package.json` or `.babelrc`: ```json // package.json "browserslist": { "production": [">0.2%", "not dead"], "development": ["last 1 chrome version", "last 1 safari version"] } ``` Then, update Babel config to include the preset: ```json // .babelrc { "presets": ["@babel/preset-env"] } ``` 2. **Include Polyfills for Missing APIs** Add `core-js` to polyfill ES6 features: ```bash npm install core-js ``` Import it in your entry file (e.g., `index.js`): ```javascript import 'core-js/stable'; ``` 3. **Use Autoprefixer for CSS Compatibility** Configure PostCSS to handle vendor prefixes: ```bash npm install autoprefixer --save-dev ``` Update `postcss.config.js`: ```javascript module.exports = { plugins: [ 'autoprefixer', ], }; ``` 4. **Test with Safari's Web Inspector** Use Safari's Developer Tools to debug: - Open Safari > Preferences > Advanced > Show Developer Tools. - Check for JavaScript errors and unsupported CSS properties. 5. **Check for Safari-Specific CSS Issues** Replace potentially problematic CSS with widely supported alternatives (e.g., use `transform: rotate` instead of `transform: rotateX`). **Note**: Verify the fix by rebuilding the app and testing in Safari. If issues persist, check for known Safari bugs (e.g., `requestAnimationFrame` throttling) or update Safari to the latest version.