diff -r 000000000000 -r 6474c204b198 browser/base/content/test/general/browser_bug495058.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/base/content/test/general/browser_bug495058.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,43 @@
+function test() {
+  waitForExplicitFinish();
+  next();
+}
+
+var uris = [
+  "about:blank",
+  "about:sessionrestore",
+  "about:privatebrowsing",
+];
+
+function next() {
+  var tab = gBrowser.addTab();
+  var uri = uris.shift();
+
+  if (uri == "about:blank") {
+    detach();
+  } else {
+    let browser = tab.linkedBrowser;
+    browser.addEventListener("load", function () {
+      browser.removeEventListener("load", arguments.callee, true);
+      detach();
+    }, true);
+    browser.loadURI(uri);
+  }
+
+  function detach() {
+    var win = gBrowser.replaceTabWithWindow(tab);
+
+    whenDelayedStartupFinished(win, function () {
+      is(win.gBrowser.currentURI.spec, uri, uri + ": uri loaded in detached tab");
+      is(win.document.activeElement, win.gBrowser.selectedBrowser, uri + ": browser is focused");
+      is(win.gURLBar.value, "", uri + ": urlbar is empty");
+      ok(win.gURLBar.placeholder, uri + ": placeholder text is present");
+
+      win.close();
+      if (uris.length)
+        next();
+      else
+        executeSoon(finish);
+    });
+  }
+}