1 files changed, 25 insertions, 0 deletions
diff --git a/browser/components/customizableui/test/browser_877447_skip_missing_ids.js b/browser/components/customizableui/test/browser_877447_skip_missing_ids.js
new file mode 100644
index 000000000..0cba7ae4f
--- /dev/null
+++ b/browser/components/customizableui/test/browser_877447_skip_missing_ids.js
@@ -0,0 +1,25 @@
+/* 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/. */
+
+"use strict";
+
+registerCleanupFunction(removeCustomToolbars);
+
+add_task(function skipMissingIDS() {
+  const kButtonId = "look-at-me-disappear-button";
+  CustomizableUI.reset();
+  ok(CustomizableUI.inDefaultState, "Should be in the default state.");
+  let btn = createDummyXULButton(kButtonId, "Gone!");
+  CustomizableUI.addWidgetToArea(kButtonId, CustomizableUI.AREA_NAVBAR);
+  ok(!CustomizableUI.inDefaultState, "Should no longer be in the default state.");
+  is(btn.parentNode.parentNode.id, CustomizableUI.AREA_NAVBAR, "Button should be in navbar");
+  btn.remove();
+  is(btn.parentNode, null, "Button is no longer in the navbar");
+  ok(CustomizableUI.inDefaultState, "Should be back in the default state, " +
+                                    "despite unknown button ID in placements.");
+});
+
+add_task(function* asyncCleanup() {
+  yield resetCustomization();
+});