Swap out babel-minify for terser (#2885)

gallery/webpack.config.js

@@ -7,6 +7,7 @@ const isProd = process.env.NODE_ENV === "production";
 const chunkFilename = isProd ? "chunk.[chunkhash].js" : "[name].chunk.js";
 const buildPath = path.resolve(__dirname, "dist");
 const publicPath = isProd ? "./" : "http://localhost:8080/";
+const latestBuild = true;
 
 module.exports = {
   mode: isProd ? "production" : "development",
@@ -16,7 +17,7 @@ module.exports = {
   entry: "./src/entrypoint.js",
   module: {
     rules: [
-      babelLoaderConfig({ latestBuild: true }),
+      babelLoaderConfig({ latestBuild }),
       {
         test: /\.css$/,
         use: "raw-loader",
@@ -32,7 +33,7 @@ module.exports = {
       },
     ],
   },
-  optimization: webpackBase.optimization,
+  optimization: webpackBase.optimization(latestBuild),
   plugins: [
     new CopyWebpackPlugin([
       "public",
@@ -51,15 +52,6 @@ module.exports = {
         to: "static/images/leaflet/",
       },
     ]),
-    isProd &&
-      new UglifyJsPlugin({
-        extractComments: true,
-        sourceMap: true,
-        uglifyOptions: {
-          // Disabling because it broke output
-          mangle: false,
-        },
-      }),
   ].filter(Boolean),
   resolve: webpackBase.resolve,
   output: {