diff --git a/toolkit/components/console/hudservice/HUDService.jsm b/toolkit/components/console/hudservice/HUDService.jsm
index b13fa51dbe00..31969dd8de30 100644
--- a/toolkit/components/console/hudservice/HUDService.jsm
+++ b/toolkit/components/console/hudservice/HUDService.jsm
@@ -3696,7 +3696,7 @@ function findCompletionBeginning(aStr)
         }
         else if (CLOSE_BODY.indexOf(c) != -1) {
           var last = bodyStack.pop();
-          if (OPEN_CLOSE_BODY[last.token] != c) {
+          if (!last || OPEN_CLOSE_BODY[last.token] != c) {
             return {
               err: "syntax error"
             };
diff --git a/toolkit/components/console/hudservice/tests/browser/Makefile.in b/toolkit/components/console/hudservice/tests/browser/Makefile.in
index 84a4de93162a..7f0fedb88ef3 100644
--- a/toolkit/components/console/hudservice/tests/browser/Makefile.in
+++ b/toolkit/components/console/hudservice/tests/browser/Makefile.in
@@ -99,6 +99,7 @@ _BROWSER_TEST_FILES = \
 	browser_webconsole_bug_588342_document_focus.js \
 	browser_webconsole_bug_595934_message_categories.js \
 	browser_webconsole_bug_601352_scroll.js \
+	browser_webconsole_bug_592442_closing_brackets.js \
 	head.js \
 	$(NULL)
 
diff --git a/toolkit/components/console/hudservice/tests/browser/browser_webconsole_bug_592442_closing_brackets.js b/toolkit/components/console/hudservice/tests/browser/browser_webconsole_bug_592442_closing_brackets.js
new file mode 100644
index 000000000000..74ee2155835c
--- /dev/null
+++ b/toolkit/components/console/hudservice/tests/browser/browser_webconsole_bug_592442_closing_brackets.js
@@ -0,0 +1,43 @@
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ *
+ * Contributor(s):
+ *  Julian Viereck <jviereck@mozilla.com>
+ *  Patrick Walton <pcwalton@mozilla.com>
+ *  Mihai Șucan <mihai.sucan@gmail.com>
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+// Tests that, when the user types an extraneous closing bracket, no error
+// appears.
+
+function test() {
+  addTab("data:text/html,test for bug 592442");
+  browser.addEventListener("load", testExtraneousClosingBrackets, true);
+}
+
+function testExtraneousClosingBrackets(aEvent) {
+  browser.removeEventListener(aEvent.type, arguments.callee, true);
+
+  openConsole();
+  let hudId = HUDService.displaysIndex()[0];
+  let jsterm = HUDService.hudWeakReferences[hudId].get().jsterm;
+
+  jsterm.setInputValue("document.getElementById)");
+
+  let error = false;
+  try {
+    jsterm.complete(jsterm.COMPLETE_HINT_ONLY);
+  }
+  catch (ex) {
+    error = true;
+  }
+
+  ok(!error, "no error was thrown when an extraneous bracket was inserted");
+
+  HUDService.deactivateHUDForContext(tab);
+  finishTest();
+}
+