diff --git a/src/components/ha-sidebar.html b/src/components/ha-sidebar.html
index 51d600dd34..0c3c2614b7 100644
--- a/src/components/ha-sidebar.html
+++ b/src/components/ha-sidebar.html
@@ -175,7 +175,7 @@
 </dom-module>
 
 <script>
-class HaSidebar extends window.hassMixins.HaFireMixin(Polymer.Element) {
+class HaSidebar extends window.hassMixins.EventsMixin(Polymer.Element) {
 
   static get is() { return 'ha-sidebar'; }
 
diff --git a/src/util/hass-mixins.html b/src/util/hass-mixins.html
index e387a88cf6..0bc486beb1 100644
--- a/src/util/hass-mixins.html
+++ b/src/util/hass-mixins.html
@@ -1,14 +1,69 @@
 <script>
+
+// Polymer legacy event helpers used courtesy of the Polymer project.
+//
+// Copyright (c) 2017 The Polymer Authors. All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
 window.hassMixins = window.hassMixins || {};
 
 /* @polymerMixin */
-window.hassMixins.HaFireMixin = function (superClass) {
-  return class extends superClass {
+window.hassMixins.EventsMixin = Polymer.dedupingMixin(
+  superClass => class extends superClass {
 
-    fire(eventName, data = {}) {
-      this.dispatchEvent(new CustomEvent(eventName,
-        Object.assign({}, data, { bubbles: true, composed: true })));
+    /**
+     * Dispatches a custom event with an optional detail value.
+     *
+     * @param {string} type Name of event type.
+     * @param {*=} detail Detail value containing event-specific
+     *   payload.
+     * @param {{ bubbles: (boolean|undefined),
+                 cancelable: (boolean|undefined),
+                 composed: (boolean|undefined) }=}
+     *  options Object specifying options.  These may include:
+     *  `bubbles` (boolean, defaults to `true`),
+     *  `cancelable` (boolean, defaults to false), and
+     *  `node` on which to fire the event (HTMLElement, defaults to `this`).
+     * @return {Event} The new event that was fired.
+     */
+    fire(type, detail, options) {
+      options = options || {};
+      detail = (detail === null || detail === undefined) ? {} : detail;
+      const event = new Event(type, {
+        bubbles: options.bubbles === undefined ? true : options.bubbles,
+        cancelable: Boolean(options.cancelable),
+        composed: options.composed === undefined ? true : options.composed
+      });
+      event.detail = detail;
+      const node = options.node || this;
+      node.dispatchEvent(event);
+      return event;
     }
-  };
-};
+  }
+);
 </script>