diff --git a/src/home-assistant.html b/src/home-assistant.html
index d827c9ea35..1e49e19037 100644
--- a/src/home-assistant.html
+++ b/src/home-assistant.html
@@ -98,9 +98,9 @@ Polymer({
   loadIcons: function () {
     // If the import fails, we'll try to import again, must be a server glitch
     // Since HTML imports only resolve once, we import another url.
-    var success = function () {
+    const success = () => {
       this.iconsLoaded = true;
-    }.bind(this);
+    };
 
     this.importHref('/static/mdi-' + this.icons + '.html',
                     success,
@@ -119,7 +119,6 @@ Polymer({
       return;
     }
     var notifications = this.$.notifications;
-    var el = this;
     this.hass = Object.assign({
       connection: conn,
       connected: true,
@@ -128,14 +127,14 @@ Polymer({
       themes: null,
       dockedSidebar: false,
       moreInfoEntityId: null,
-      callService: function (domain, service, serviceData) {
-        return conn.callService(domain, service, serviceData || {})
-          .then(function () {
+      callService: (domain, service, serviceData) =>
+        conn.callService(domain, service, serviceData || {})
+          .then(() => {
             var message;
             var name;
-            if (serviceData.entity_id && el.hass.states &&
-                el.hass.states[serviceData.entity_id]) {
-              name = window.hassUtil.computeStateName(el.hass.states[serviceData.entity_id]);
+            if (serviceData.entity_id && this.hass.states &&
+                this.hass.states[serviceData.entity_id]) {
+              name = window.hassUtil.computeStateName(this.hass.states[serviceData.entity_id]);
             }
             if (service === 'turn_on' && serviceData.entity_id) {
               message = 'Turned on ' + (name || serviceData.entity_id) + '.';
@@ -150,52 +149,51 @@ Polymer({
             notifications.showNotification(
               'Failed to call service ' + domain + '/' + service);
             return Promise.reject();
-          });
-      },
-      callApi: function (method, path, parameters) {
+          }),
+      callApi: (method, path, parameters) => {
         var host = window.location.protocol + '//' + window.location.host;
         var auth = conn.options.authToken ? conn.options : {};
         return window.hassCallApi(host, auth, method, path, parameters);
       },
     }, this.$.storage.getStoredState());
 
-    var reconnected = function () {
+    var reconnected = () => {
       this.hass = Object.assign({}, this.hass, { connected: true });
-    }.bind(this);
+    };
 
     conn.addEventListener('ready', reconnected);
 
-    var disconnected = function () {
+    var disconnected = () => {
       this.hass = Object.assign({}, this.hass, { connected: false });
-    }.bind(this);
+    };
 
     conn.addEventListener('disconnected', disconnected);
 
     var unsubEntities;
 
-    window.HAWS.subscribeEntities(conn, function (states) {
+    window.HAWS.subscribeEntities(conn, (states) => {
       this.hass = Object.assign({}, this.hass, { states: states });
-    }.bind(this)).then(function (unsub) {
+    }).then(function (unsub) {
       unsubEntities = unsub;
     });
 
     var unsubConfig;
 
-    window.HAWS.subscribeConfig(conn, function (config) {
+    window.HAWS.subscribeConfig(conn, (config) => {
       this.hass = Object.assign({}, this.hass, { config: config });
-    }.bind(this)).then(function (unsub) {
+    }).then(function (unsub) {
       unsubConfig = unsub;
     });
 
     var unsubThemes;
 
-    this.hass.callApi('get', 'themes').then(function (themes) {
-      el.hass.themes = themes;
-      window.hassUtil.applyThemesOnElement(el, themes);
+    this.hass.callApi('get', 'themes').then((themes) => {
+      this.hass.themes = themes;
+      window.hassUtil.applyThemesOnElement(this, themes);
     });
-    conn.subscribeEvents(function (event) {
-      el.hass.themes = event.data;
-      window.hassUtil.applyThemesOnElement(el, event.data);
+    conn.subscribeEvents((event) => {
+      this.hass.themes = event.data;
+      window.hassUtil.applyThemesOnElement(this, event.data);
     }, 'themes_updated').then(function (unsub) {
       unsubThemes = unsub;
     });
@@ -212,12 +210,10 @@ Polymer({
   handleConnectionPromise: function (prom) {
     if (!prom) return;
 
-    var el = this;
-
-    prom.then(function (conn) {
-      el.connection = conn;
-    }, function () {
-      el.connectionPromise = null;
+    prom.then((conn) => {
+      this.connection = conn;
+    }, () => {
+      this.connectionPromise = null;
     });
   },
 
@@ -256,10 +252,6 @@ Polymer({
 
   ready: function () {
     this.loadIcons();
-
-    if (this.connectionPromise !== null) {
-      this.handleConnectionPromise(this.connectionPromise);
-    }
   },
 });
 </script>
diff --git a/src/layouts/partial-cards.html b/src/layouts/partial-cards.html
index abd4c94741..244d9eafd6 100644
--- a/src/layouts/partial-cards.html
+++ b/src/layouts/partial-cards.html
@@ -226,7 +226,7 @@ Polymer({
   },
 
   areTabsHidden: function (views, showTabs) {
-    return !views.length || !showTabs;
+    return !views || !views.length || !showTabs;
   },
 
   /**