diff --git a/packages/react-scripts/config/webpack.config.prod.js b/packages/react-scripts/config/webpack.config.prod.js
index 01e9d6fe796..f36c3d56b1e 100644
--- a/packages/react-scripts/config/webpack.config.prod.js
+++ b/packages/react-scripts/config/webpack.config.prod.js
@@ -258,15 +258,10 @@ module.exports = {
     // Minify the code.
     new webpack.optimize.UglifyJsPlugin({
       compress: {
-        screw_ie8: true, // React doesn't support IE8
         warnings: false,
       },
-      mangle: {
-        screw_ie8: true,
-      },
       output: {
         comments: false,
-        screw_ie8: true,
       },
       sourceMap: true,
     }),