diff --git a/common/web/lm-worker/build-wrap-and-minify.js b/common/web/lm-worker/build-wrap-and-minify.js
index 009a8f496c0..1572238b7a8 100644
--- a/common/web/lm-worker/build-wrap-and-minify.js
+++ b/common/web/lm-worker/build-wrap-and-minify.js
@@ -35,6 +35,7 @@ if(MINIFY) {
     sourcesContent: DEBUG,
     minify: true,
     keepNames: true,
+    target: 'es5',
     outfile: `build/lib/worker-main.polyfilled.min.js`
   });
 }