Bug 938980 - [Australis] Restore Defaults will not reshow the address bar if it has been hidden through channel switching. r=Gijs

browser/components/customizableui/src/CustomizableUI.jsm

@@ -359,6 +359,12 @@ let CustomizableUIInternal = {
 
     this.beginBatchUpdate();
 
+    // Restore nav-bar visibility since it may have been hidden
+    // through a migration path (bug 938980) or an add-on.
+    if (aArea == CustomizableUI.AREA_NAVBAR) {
+      aAreaNode.collapsed = false;
+    }
+
     let currentNode = container.firstChild;
     let placementsToRemove = new Set();
     for (let id of aPlacements) {

browser/components/customizableui/test/browser.ini

@@ -35,4 +35,5 @@ skip-if = true
 # Because this test is about the menubar, it can't be run on mac
 skip-if = os == "mac"
 
+[browser_938980_navbar_collapsed.js]
 [browser_panel_toggle.js]

browser/components/customizableui/test/browser_938980_navbar_collapsed.js

@@ -0,0 +1,26 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+let gTests = [
+  {
+    desc: "Customization reset should restore visibility to default-visible toolbars.",
+    setup: null,
+    run: function() {
+      let navbar = document.getElementById("nav-bar");
+      is(navbar.collapsed, false, "Test should start with navbar visible");
+      navbar.collapsed = true;
+      is(navbar.collapsed, true, "navbar should be hidden now");
+
+      yield resetCustomization();
+
+      is(navbar.collapsed, false, "Customization reset should restore visibility to the navbar");
+    },
+    teardown: null
+  },
+];
+
+function test() {
+  waitForExplicitFinish();
+  runTests(gTests);
+}