--- a/mobile/android/base/java/org/mozilla/gecko/GeckoApp.java
+++ b/mobile/android/base/java/org/mozilla/gecko/GeckoApp.java
@@ -603,18 +603,26 @@ public abstract class GeckoApp extends G
             return true;
         }
 
         return super.onKeyDown(keyCode, event);
     }
 
     @Override
     protected void onSaveInstanceState(Bundle outState) {
+        // Through the GeckoActivityMonitor, this will flush tabs if the whole
+        // application is going into the background.
         super.onSaveInstanceState(outState);
 
+        // If on the other hand we're merely switching to a different activity
+        // within our app, we need to trigger a tabs flush ourselves.
+        if (!isApplicationInBackground()) {
+            EventDispatcher.getInstance().dispatch("Session:FlushTabs", null);
+        }
+
         outState.putBoolean(SAVED_STATE_IN_BACKGROUND, isApplicationInBackground());
         outState.putString(SAVED_STATE_PRIVATE_SESSION, mPrivateBrowsingSession);
     }
 
     public void addTab() { }
 
     public void addPrivateTab() { }
 

--- a/mobile/android/base/java/org/mozilla/gecko/GeckoApplication.java
+++ b/mobile/android/base/java/org/mozilla/gecko/GeckoApplication.java
@@ -174,16 +174,17 @@ public class GeckoApplication extends Ap
     public void onApplicationBackground() {
         mInBackground = true;
 
         // Notify Gecko that we are pausing; the cache service will be
         // shutdown, closing the disk cache cleanly. If the android
         // low memory killer subsequently kills us, the disk cache will
         // be left in a consistent state, avoiding costly cleanup and
         // re-creation.
+        EventDispatcher.getInstance().dispatch("Session:FlushTabs", null);
         GeckoThread.onPause();
         mPausedGecko = true;
 
         final BrowserDB db = BrowserDB.from(this);
         ThreadUtils.postToBackgroundThread(new Runnable() {
             @Override
             public void run() {
                 db.expireHistory(getContentResolver(), BrowserContract.ExpirePriority.NORMAL);

--- a/mobile/android/components/SessionStore.js
+++ b/mobile/android/components/SessionStore.js
@@ -197,16 +197,27 @@ SessionStore.prototype = {
         this._sendClosedTabsToJava(Services.wm.getMostRecentWindow("navigator:browser"));
         break;
 
       case "ClosedTabs:StopNotifications":
         this._notifyClosedTabs = false;
         log("ClosedTabs:StopNotifications");
         break;
 
+      case "Session:FlushTabs":
+        // We receive this notification when the activity or application is going into
+        // the background. If the application is backgrounded, it may be terminated at
+        // any point without notice; therefore, we must synchronously write out any
+        // pending save state to ensure that this data does not get lost.
+        log("Session:FlushTabs");
+        if (this._loadState == STATE_RUNNING) {
+          this.flushPendingState();
+        }
+        break;
+
       case "Session:Restore": {
         EventDispatcher.instance.unregisterListener(this, "Session:Restore");
         if (data) {
           // Be ready to handle any restore failures by making sure we have a valid tab opened
           let window = Services.wm.getMostRecentWindow("navigator:browser");
           let restoreCleanup = (aSubject, aTopic, aData) => {
               Services.obs.removeObserver(restoreCleanup, "sessionstore-windows-restored");
 
@@ -261,32 +272,32 @@ SessionStore.prototype = {
 
   observe: function ss_observe(aSubject, aTopic, aData) {
     let observerService = Services.obs;
     switch (aTopic) {
       case "app-startup":
         EventDispatcher.instance.registerListener(this, [
           "ClosedTabs:StartNotifications",
           "ClosedTabs:StopNotifications",
+          "Session:FlushTabs",
           "Session:Restore",
           "Session:RestoreRecentTabs",
           "Tab:KeepZombified",
           "Tabs:OpenMultiple",
         ]);
         observerService.addObserver(this, "final-ui-startup", true);
         observerService.addObserver(this, "domwindowopened", true);
         observerService.addObserver(this, "domwindowclosed", true);
         observerService.addObserver(this, "browser:purge-session-history", true);
         observerService.addObserver(this, "browser:purge-session-tabs", true);
         observerService.addObserver(this, "quit-application-requested", true);
         observerService.addObserver(this, "quit-application-proceeding", true);
         observerService.addObserver(this, "quit-application", true);
         observerService.addObserver(this, "Session:NotifyLocationChange", true);
         observerService.addObserver(this, "Content:HistoryChange", true);
-        observerService.addObserver(this, "application-background", true);
         observerService.addObserver(this, "application-foreground", true);
         observerService.addObserver(this, "last-pb-context-exited", true);
         break;
       case "final-ui-startup":
         observerService.removeObserver(this, "final-ui-startup");
         this.init();
         break;
       case "domwindowopened": {
@@ -370,26 +381,16 @@ SessionStore.prototype = {
           browser.__SS_historyChange =
             window.setTimeout(() => {
               delete browser.__SS_historyChange;
               this.onTabLoad(window, browser);
             }, 0);
         }
         break;
       }
-      case "application-background":
-        // We receive this notification when Android's onPause callback is
-        // executed. After onPause, the application may be terminated at any
-        // point without notice; therefore, we must synchronously write out any
-        // pending save state to ensure that this data does not get lost.
-        log("application-background");
-        if (this._loadState == STATE_RUNNING) {
-          this.flushPendingState();
-        }
-        break;
       case "application-foreground":
         log("application-foreground");
         // If we skipped restoring a zombified tab before backgrounding,
         // we might have to do it now instead.
         let window = Services.wm.getMostRecentWindow("navigator:browser");
         if (window && window.BrowserApp) { // Might not yet be ready during a cold startup.
           let tab = window.BrowserApp.selectedTab;
           if (tab) { // Can be null if closing a tab triggered an activity switch.