--- a/mobile/android/base/java/org/mozilla/gecko/Tabs.java
+++ b/mobile/android/base/java/org/mozilla/gecko/Tabs.java
@@ -967,17 +967,17 @@ public class Tabs implements BundleEvent
 
         data.putString("url", url);
         data.putString("engine", searchEngine);
         data.putInt("parentId", parentId);
         data.putBoolean("userEntered", userEntered);
         data.putBoolean("isPrivate", isPrivate);
         data.putBoolean("pinned", (flags & LOADURL_PINNED) != 0);
         data.putBoolean("desktopMode", desktopMode);
-        data.putBoolean("customTab", customTab);
+        data.putString("tabType", type.name());
 
         final boolean needsNewTab;
         final String applicationId = (intent == null) ? null :
                 intent.getStringExtra(Browser.EXTRA_APPLICATION_ID);
         if (applicationId == null) {
             needsNewTab = (flags & LOADURL_NEW_TAB) != 0;
         } else {
             // If you modify this code, be careful that intent != null.

--- a/mobile/android/chrome/content/browser.js
+++ b/mobile/android/chrome/content/browser.js
@@ -1858,17 +1858,17 @@ var BrowserApp = {
           selected: ("selected" in data) ? data.selected : !delayLoad,
           parentId: ("parentId" in data) ? data.parentId : -1,
           flags: flags,
           tabID: data.tabID,
           isPrivate: (data.isPrivate === true),
           pinned: (data.pinned === true),
           delayLoad: (delayLoad === true),
           desktopMode: (data.desktopMode === true),
-          customTab: ("customTab" in data) ? data.customTab : false
+          tabType: ("tabType" in data) ? data.tabType : "BROWSING"
         };
 
         params.userRequested = url;
 
         if (data.engine) {
           let engine = Services.search.getEngineByName(data.engine);
           if (engine) {
             let submission = engine.getSubmission(url);
@@ -3381,18 +3381,18 @@ nsBrowserAccess.prototype = {
     // along with other OPEN_ values that create a new tab.
     let newTab = (aWhere == Ci.nsIBrowserDOMWindow.OPEN_NEWWINDOW ||
                   aWhere == Ci.nsIBrowserDOMWindow.OPEN_NEWTAB ||
                   aWhere == Ci.nsIBrowserDOMWindow.OPEN_SWITCHTAB);
     let isPrivate = false;
 
     if (aOpener != null) {
       let parent = BrowserApp.getTabForWindow(aOpener.top);
-      if ((parent != null) && ("isCustomTab" in parent)) {
-        newTab = newTab && !parent.isCustomTab;
+      if (parent != null) {
+        newTab = newTab && parent.tabType != "CUSTOMTAB";
       }
     }
 
     if (newTab) {
       let parentId = -1;
       if (!isExternal && aOpener) {
         let parent = BrowserApp.getTabForWindow(aOpener.top);
         if (parent) {
@@ -3551,16 +3551,19 @@ Tab.prototype = {
 
     // When the tab is stubbed from Java, there's a window between the stub
     // creation and the tab creation in Gecko where the stub could be removed
     // or the selected tab can change (which is easiest to hit during startup).
     // To prevent these races, we need to differentiate between tab stubs from
     // Java and new tabs from Gecko.
     let stub = false;
 
+    // The authoritative list of possible tab types is the TabType enum in Tab.java.
+    this.type = "tabType" in aParams ? aParams.tabType : "BROWSING";
+
     if (!aParams.zombifying) {
       if ("tabID" in aParams) {
         this.id = aParams.tabID;
         stub = true;
       } else {
         let jenv = JNI.GetForThread();
         let jTabs = JNI.LoadClass(jenv, "org.mozilla.gecko.Tabs", {
           static_methods: [
@@ -3573,17 +3576,17 @@ Tab.prototype = {
 
       this.desktopMode = ("desktopMode" in aParams) ? aParams.desktopMode : false;
       this._parentId = ("parentId" in aParams && typeof aParams.parentId == "number")
                       ? aParams.parentId : -1;
 
       let message = {
         type: "Tab:Added",
         tabID: this.id,
-        tabType: "BROWSING",
+        tabType: this.type,
         uri: truncate(uri, MAX_URI_LENGTH),
         parentId: this.parentId,
         tabIndex: ("tabIndex" in aParams) ? aParams.tabIndex : -1,
         external: ("external" in aParams) ? aParams.external : false,
         selected: ("selected" in aParams || aParams.cancelEditMode === true)
                   ? aParams.selected !== false || aParams.cancelEditMode === true : true,
         cancelEditMode: aParams.cancelEditMode === true,
         title: truncate(title, MAX_TITLE_LENGTH),
@@ -3653,17 +3656,16 @@ Tab.prototype = {
       let flags = "flags" in aParams ? aParams.flags : Ci.nsIWebNavigation.LOAD_FLAGS_NONE;
       let postData = ("postData" in aParams && aParams.postData) ? aParams.postData.value : null;
       let referrerURI = "referrerURI" in aParams ? aParams.referrerURI : null;
       let charset = "charset" in aParams ? aParams.charset : null;
 
       // The search term the user entered to load the current URL
       this.userRequested = "userRequested" in aParams ? aParams.userRequested : "";
       this.isSearch = "isSearch" in aParams ? aParams.isSearch : false;
-      this.isCustomTab = "customTab" in aParams ? aParams.customTab : false;
 
       try {
         this.browser.loadURIWithFlags(aURL, flags, referrerURI, charset, postData);
       } catch(e) {
         let message = {
           type: "Content:LoadError",
           tabID: this.id
         };

--- a/mobile/android/components/SessionStore.js
+++ b/mobile/android/components/SessionStore.js
@@ -1111,16 +1111,17 @@ SessionStore.prototype = {
     let tab = aWindow.BrowserApp.getTabForBrowser(aBrowser);
     tabData.entries = aHistory.entries;
     tabData.index = aHistory.index;
     tabData.attributes = { image: aBrowser.mIconURL };
     tabData.desktopMode = tab.desktopMode;
     tabData.isPrivate = aBrowser.docShell.QueryInterface(Ci.nsILoadContext).usePrivateBrowsing;
     tabData.tabId = tab.id;
     tabData.parentId = tab.parentId;
+    tabData.type = tab.type;
 
     aBrowser.__SS_data = tabData;
   },
 
   _collectWindowData: function ss__collectWindowData(aWindow) {
     // Ignore windows not tracked by SessionStore
     if (!aWindow.__SSID || !this._windows[aWindow.__SSID]) {
       return;