diff -r 000000000000 -r 6474c204b198 browser/base/content/test/general/browser_bug749738.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/base/content/test/general/browser_bug749738.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,36 @@
+/* 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";
+
+const DUMMY_PAGE = "http://example.org/browser/browser/base/content/test/general/dummy_page.html";
+
+function test() {
+  waitForExplicitFinish();
+
+  let tab = gBrowser.addTab();
+  gBrowser.selectedTab = tab;
+
+  load(tab, DUMMY_PAGE, function() {
+    gFindBar.onFindCommand();
+    EventUtils.sendString("Dummy");
+    gBrowser.removeTab(tab);
+
+    try {
+      gFindBar.close();
+      ok(true, "findbar.close should not throw an exception");
+    } catch(e) {
+      ok(false, "findbar.close threw exception: " + e);
+    }
+    finish();
+  });
+}
+
+function load(aTab, aUrl, aCallback) {
+  aTab.linkedBrowser.addEventListener("load", function onload(aEvent) {
+    aEvent.currentTarget.removeEventListener("load", onload, true);
+    waitForFocus(aCallback, content);
+  }, true);
+  aTab.linkedBrowser.loadURI(aUrl);
+}