--- a/browser/components/customizableui/test/browser.ini
+++ b/browser/components/customizableui/test/browser.ini
@@ -1,15 +1,16 @@
 [DEFAULT]
 support-files =
   head.js
   support/test_967000_charEncoding_page.html
   support/feeds_test_page.html
   support/test-feed.xml
 
+[browser_no_saved_state.js]
 [browser_694291_searchbar_preference.js]
 [browser_873501_handle_specials.js]
 [browser_876926_customize_mode_wrapping.js]
 [browser_876944_customize_mode_create_destroy.js]
 [browser_877006_missing_view.js]
 [browser_877178_unregisterArea.js]
 [browser_877447_skip_missing_ids.js]
 [browser_878452_drag_to_panel.js]

new file mode 100644
--- /dev/null
+++ b/browser/components/customizableui/test/browser_no_saved_state.js
@@ -0,0 +1,10 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+function test() {
+  const kPrefCustomizationState = "browser.uiCustomization.state";
+  is(Services.prefs.getCharPref(kPrefCustomizationState), "",
+     "We shouldn't have any saved state by default.");
+}