diff --git a/background.html b/background.html
index dd6ae604e..c0da6a528 100644
--- a/background.html
+++ b/background.html
@@ -449,7 +449,6 @@
   <script type='text/javascript' src='js/signal_protocol_store.js'></script>
   <script type='text/javascript' src='js/libtextsecure.js'></script>
 
-  <script type='text/javascript' src='js/focus_listener.js'></script>
   <script type='text/javascript' src='js/notifications.js'></script>
   <script type='text/javascript' src='js/delivery_receipts.js'></script>
   <script type='text/javascript' src='js/read_receipts.js'></script>
diff --git a/js/background.js b/js/background.js
index 6eda29047..3e52cd598 100644
--- a/js/background.js
+++ b/js/background.js
@@ -40,6 +40,43 @@
     false
   );
 
+  // Idle timer - you're active for ACTIVE_TIMEOUT after one of these events
+  const ACTIVE_TIMEOUT = 15 * 1000;
+  const ACTIVE_EVENTS = [
+    'click',
+    'keypress',
+    'mousedown',
+    'mousemove',
+    // 'scroll', // this is triggered by Timeline re-renders, can't use
+    'touchstart',
+    'wheel',
+  ];
+
+  const LISTENER_DEBOUNCE = 5 * 1000;
+  let activeHandlers = [];
+  let activeTimestamp = Date.now();
+
+  window.resetActiveTimer = _.throttle(() => {
+    const previouslyActive = window.isActive();
+    activeTimestamp = Date.now();
+    if (!previouslyActive) {
+      activeHandlers.forEach(handler => handler());
+    }
+  }, LISTENER_DEBOUNCE);
+
+  ACTIVE_EVENTS.forEach(name => {
+    document.addEventListener(name, window.resetActiveTimer, true);
+  });
+
+  window.isActive = () => {
+    const now = Date.now();
+    return now <= activeTimestamp + ACTIVE_TIMEOUT;
+  };
+  window.registerForActive = handler => activeHandlers.push(handler);
+  window.unregisterForActive = handler => {
+    activeHandlers = activeHandlers.filter(item => item !== handler);
+  };
+
   // Load these images now to ensure that they don't flicker on first use
   window.Signal.EmojiLib.preloadImages();
   const images = [];
@@ -712,7 +749,7 @@
       }
     });
 
-    window.addEventListener('focus', () => Whisper.Notifications.clear());
+    window.registerForActive(() => Whisper.Notifications.clear());
     window.addEventListener('unload', () => Whisper.Notifications.fastClear());
 
     Whisper.events.on('showConversation', (id, messageId) => {
diff --git a/js/focus_listener.js b/js/focus_listener.js
deleted file mode 100644
index c9a728233..000000000
--- a/js/focus_listener.js
+++ /dev/null
@@ -1,14 +0,0 @@
-// eslint-disable-next-line func-names
-(function() {
-  'use strict';
-
-  let windowFocused = false;
-  window.addEventListener('blur', () => {
-    windowFocused = false;
-  });
-  window.addEventListener('focus', () => {
-    windowFocused = true;
-  });
-
-  window.isFocused = () => windowFocused;
-})();
diff --git a/js/models/conversations.js b/js/models/conversations.js
index edaa94ac1..e9bc61d42 100644
--- a/js/models/conversations.js
+++ b/js/models/conversations.js
@@ -334,7 +334,7 @@
           this.id,
           [model.getReduxData()],
           isNewMessage,
-          document.hasFocus()
+          window.isActive()
         );
       }
 
diff --git a/js/notifications.js b/js/notifications.js
index 7c0fb39ae..8df33aa42 100644
--- a/js/notifications.js
+++ b/js/notifications.js
@@ -3,7 +3,6 @@
 
 /* global drawAttention: false */
 /* global i18n: false */
-/* global isFocused: false */
 /* global Signal: false */
 /* global storage: false */
 /* global Whisper: false */
@@ -54,7 +53,7 @@
       }
 
       const { isEnabled } = this;
-      const isAppFocused = isFocused();
+      const isAppFocused = window.isActive();
       const isAudioNotificationEnabled =
         storage.get('audio-notification') || false;
       const isAudioNotificationSupported = Settings.isAudioNotificationSupported();
diff --git a/js/views/app_view.js b/js/views/app_view.js
index 162f0b69f..9321cfd3a 100644
--- a/js/views/app_view.js
+++ b/js/views/app_view.js
@@ -166,7 +166,7 @@
       if (!$.contains(this.el, this.inboxView.el)) {
         this.openView(this.inboxView);
       }
-      window.focus(); // FIXME
+
       return Promise.resolve();
     },
     onEmpty() {
diff --git a/js/views/conversation_view.js b/js/views/conversation_view.js
index d30dd663b..bd8115c77 100644
--- a/js/views/conversation_view.js
+++ b/js/views/conversation_view.js
@@ -442,7 +442,7 @@
             id,
             models.map(model => model.getReduxData()),
             isNewMessage,
-            document.hasFocus()
+            window.isActive()
           );
         } catch (error) {
           setMessagesLoading(conversationId, true);
@@ -493,7 +493,7 @@
             id,
             models.map(model => model.getReduxData()),
             isNewMessage,
-            document.hasFocus()
+            window.isActive()
           );
         } catch (error) {
           setMessagesLoading(conversationId, false);
@@ -502,10 +502,8 @@
           finish();
         }
       };
-      const markMessageRead = async (messageId, forceFocus) => {
-        // We need a forceFocus parameter because the BrowserWindow focus event fires
-        //   before the document realizes that it has focus.
-        if (!document.hasFocus() && !forceFocus) {
+      const markMessageRead = async messageId => {
+        if (!window.isActive()) {
           return;
         }
 
diff --git a/preload.js b/preload.js
index 369fb10ca..8e350791b 100644
--- a/preload.js
+++ b/preload.js
@@ -10,14 +10,6 @@ const { remote } = electron;
 const { app } = remote;
 const { systemPreferences } = remote.require('electron');
 
-const browserWindow = remote.getCurrentWindow();
-let focusHandlers = [];
-browserWindow.on('focus', () => focusHandlers.forEach(handler => handler()));
-window.registerForFocus = handler => focusHandlers.push(handler);
-window.unregisterForFocus = handler => {
-  focusHandlers = focusHandlers.filter(item => item !== handler);
-};
-
 // Waiting for clients to implement changes on receive side
 window.ENABLE_STICKER_SEND = true;
 window.TIMESTAMP_VALIDATION = false;
diff --git a/test/index.html b/test/index.html
index e51e22adc..9c013d1a6 100644
--- a/test/index.html
+++ b/test/index.html
@@ -476,7 +476,6 @@
   <script type='text/javascript' src='../js/expiring_messages.js' data-cover></script>
   <script type='text/javascript' src='../js/expiring_tap_to_view_messages.js' data-cover></script>
   <script type='text/javascript' src='../js/notifications.js' data-cover></script>
-  <script type='text/javascript' src='../js/focus_listener.js'></script>
 
   <script type="text/javascript" src="../js/chromium.js" data-cover></script>
 
diff --git a/ts/components/conversation/Timeline.tsx b/ts/components/conversation/Timeline.tsx
index 697a68fd2..5220dd487 100644
--- a/ts/components/conversation/Timeline.tsx
+++ b/ts/components/conversation/Timeline.tsx
@@ -61,7 +61,7 @@ type PropsActionsType = {
   loadOlderMessages: (messageId: string) => unknown;
   loadNewerMessages: (messageId: string) => unknown;
   loadNewestMessages: (messageId: string) => unknown;
-  markMessageRead: (messageId: string, forceFocus?: boolean) => unknown;
+  markMessageRead: (messageId: string) => unknown;
 } & MessageActionsType &
   SafetyNumberActionsType;
 
@@ -402,7 +402,7 @@ export class Timeline extends React.PureComponent<Props, State> {
 
   // tslint:disable-next-line member-ordering cyclomatic-complexity
   public updateWithVisibleRows = debounce(
-    (forceFocus?: boolean) => {
+    () => {
       const {
         unreadCount,
         haveNewest,
@@ -426,7 +426,7 @@ export class Timeline extends React.PureComponent<Props, State> {
         return;
       }
 
-      markMessageRead(newest.id, forceFocus);
+      markMessageRead(newest.id);
 
       const rowCount = this.getRowCount();
 
@@ -710,19 +710,14 @@ export class Timeline extends React.PureComponent<Props, State> {
   public componentDidMount() {
     this.updateWithVisibleRows();
     // @ts-ignore
-    window.registerForFocus(this.forceFocusVisibleRowUpdate);
+    window.registerForActive(this.updateWithVisibleRows);
   }
 
   public componentWillUnmount() {
     // @ts-ignore
-    window.unregisterForFocus(this.forceFocusVisibleRowUpdate);
+    window.unregisterForActive(this.updateWithVisibleRows);
   }
 
-  public forceFocusVisibleRowUpdate = () => {
-    const forceFocus = true;
-    this.updateWithVisibleRows(forceFocus);
-  };
-
   // tslint:disable-next-line cyclomatic-complexity max-func-body-length
   public componentDidUpdate(prevProps: Props) {
     const {
diff --git a/ts/state/ducks/conversations.ts b/ts/state/ducks/conversations.ts
index a39eb86b4..264777c72 100644
--- a/ts/state/ducks/conversations.ts
+++ b/ts/state/ducks/conversations.ts
@@ -160,7 +160,7 @@ export type MessagesAddedActionType = {
     conversationId: string;
     messages: Array<MessageType>;
     isNewMessage: boolean;
-    isFocused: boolean;
+    isActive: boolean;
   };
 };
 export type MessagesResetActionType = {
@@ -357,7 +357,7 @@ function messagesAdded(
   conversationId: string,
   messages: Array<MessageType>,
   isNewMessage: boolean,
-  isFocused: boolean
+  isActive: boolean
 ): MessagesAddedActionType {
   return {
     type: 'MESSAGES_ADDED',
@@ -365,7 +365,7 @@ function messagesAdded(
       conversationId,
       messages,
       isNewMessage,
-      isFocused,
+      isActive,
     },
   };
 }
@@ -870,12 +870,7 @@ export function reducer(
     };
   }
   if (action.type === 'MESSAGES_ADDED') {
-    const {
-      conversationId,
-      isFocused,
-      isNewMessage,
-      messages,
-    } = action.payload;
+    const { conversationId, isActive, isNewMessage, messages } = action.payload;
     const { messagesByConversation, messagesLookup } = state;
 
     const existingConversation = messagesByConversation[conversationId];
@@ -937,7 +932,7 @@ export function reducer(
     const newMessageIds = difference(newIds, existingConversation.messageIds);
     const { isNearBottom } = existingConversation;
 
-    if ((!isNearBottom || !isFocused) && !oldestUnread) {
+    if ((!isNearBottom || !isActive) && !oldestUnread) {
       const oldestId = newMessageIds.find(messageId => {
         const message = lookup[messageId];