diff --git a/core/src/polyfills.js b/core/src/polyfills.js
index <HASH>..<HASH> 100644
--- a/core/src/polyfills.js
+++ b/core/src/polyfills.js
@@ -6,10 +6,10 @@
 // because import statements are hoisted during compilation.
 import './polyfill-switches';
 
-// Polyfill Custom Elements v1 with global namespace pollution
-import '@webcomponents/custom-elements';
-
 // Polyfill ECMAScript standard features with global namespace pollution
 import 'core-js/fn/object/set-prototype-of';
 import 'core-js/fn/set';
 import 'core-js/fn/map';
+
+// Polyfill Custom Elements v1 with global namespace pollution
+import '@webcomponents/custom-elements';
fix(polyfills): Load ECMAScript standard features polyfills before Custom Elements polyfill.