diff -r 000000000000 -r 6474c204b198 browser/base/content/test/general/browser_urlbarEnter.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/base/content/test/general/browser_urlbarEnter.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,69 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+const TEST_VALUE = "example.com/\xF7?\xF7";
+const START_VALUE = "example.com/%C3%B7?%C3%B7";
+
+function test() {
+  waitForExplicitFinish();
+  runNextTest();
+}
+
+function locationBarEnter(aEvent, aClosure) {
+  executeSoon(function() {
+    gURLBar.focus();
+    EventUtils.synthesizeKey("VK_RETURN", aEvent);
+    addPageShowListener(aClosure);
+  });
+}
+
+function runNextTest() {
+  let test = gTests.shift();
+  if (!test) {
+    finish();
+    return;
+  }
+  
+  info("Running test: " + test.desc);
+  let tab = gBrowser.selectedTab = gBrowser.addTab(START_VALUE);
+  addPageShowListener(function() {
+    locationBarEnter(test.event, function() {
+      test.check(tab);
+
+      // Clean up
+      while (gBrowser.tabs.length > 1)
+        gBrowser.removeTab(gBrowser.selectedTab)
+      runNextTest();
+    });
+  });
+}
+
+let gTests = [
+  { desc: "Simple return keypress",
+    event: {},
+    check: checkCurrent
+  },
+
+  { desc: "Alt+Return keypress",
+    event: { altKey: true },
+    check: checkNewTab,
+  },
+]
+
+function checkCurrent(aTab) {
+  is(gURLBar.value, TEST_VALUE, "Urlbar should preserve the value on return keypress");
+  is(gBrowser.selectedTab, aTab, "New URL was loaded in the current tab");
+}
+
+function checkNewTab(aTab) {
+  is(gURLBar.value, TEST_VALUE, "Urlbar should preserve the value on return keypress");
+  isnot(gBrowser.selectedTab, aTab, "New URL was loaded in a new tab");
+}
+
+function addPageShowListener(aFunc) {
+  gBrowser.selectedBrowser.addEventListener("pageshow", function loadListener() {
+    gBrowser.selectedBrowser.removeEventListener("pageshow", loadListener, false);
+    aFunc();
+  });
+}
+