diff --git a/packages/kbn-optimizer/src/worker/webpack.config.ts b/packages/kbn-optimizer/src/worker/webpack.config.ts
index 96a17a6ae7229..b5da9566878e1 100644
--- a/packages/kbn-optimizer/src/worker/webpack.config.ts
+++ b/packages/kbn-optimizer/src/worker/webpack.config.ts
@@ -280,6 +280,14 @@ export function getWebpackConfig(
             plugins: ['@babel/plugin-transform-logical-assignment-operators'],
           },
         },
+        {
+          test: /node_modules[\/\\]launchdarkly[^\/\\]+[\/\\].*.js$/,
+          loaders: 'babel-loader',
+          options: {
+            envName: worker.dist ? 'production' : 'development',
+            presets: [BABEL_PRESET],
+          },
+        },
         {
           test: /\.(html|md|txt|tmpl)$/,
           use: {