diff --git a/src/util/legacy-support.js b/src/util/legacy-support.js
index 79b1ec7399..7bf8c58649 100644
--- a/src/util/legacy-support.js
+++ b/src/util/legacy-support.js
@@ -4,6 +4,8 @@
  */
 import { PolymerElement } from '@polymer/polymer/polymer-element.js';
 import { Polymer } from '@polymer/polymer/polymer-legacy.js';
+import { html } from '@polymer/polymer/lib/utils/html-tag.js';
 
 Polymer.Element = PolymerElement;
+Polymer.html = html;
 window.Polymer = Polymer;