diff -r 000000000000 -r 6474c204b198 browser/devtools/scratchpad/test/browser_scratchpad_wrong_window_focus.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/devtools/scratchpad/test/browser_scratchpad_wrong_window_focus.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,85 @@
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+/* Bug 661762 */
+
+
+function test()
+{
+  waitForExplicitFinish();
+
+  // To test for this bug we open a Scratchpad window, save its
+  // reference and then open another one. This way the first window
+  // loses its focus.
+  //
+  // Then we open a web console and execute a console.log statement
+  // from the first Scratch window (that's why we needed to save its
+  // reference).
+  //
+  // Then we wait for our message to appear in the console and click
+  // on the location link. After that we check which Scratchpad window
+  // is currently active (it should be the older one).
+
+  gBrowser.selectedTab = gBrowser.addTab();
+  gBrowser.selectedBrowser.addEventListener("load", function onLoad() {
+    gBrowser.selectedBrowser.removeEventListener("load", onLoad, true);
+
+    openScratchpad(function () {
+      let sw = gScratchpadWindow;
+      let {devtools} = Cu.import("resource://gre/modules/devtools/Loader.jsm", {});
+
+      openScratchpad(function () {
+        let target = devtools.TargetFactory.forTab(gBrowser.selectedTab);
+        gDevTools.showToolbox(target, "webconsole").then((toolbox) => {
+          let hud = toolbox.getCurrentPanel().hud;
+          hud.jsterm.clearOutput(true);
+          testFocus(sw, hud);
+        });
+      });
+    });
+  }, true);
+
+  content.location = "data:text/html;charset=utf8,<p>test window focus for Scratchpad.";
+}
+
+function testFocus(sw, hud) {
+  let sp = sw.Scratchpad;
+
+  function onMessage(event, messages) {
+    let msg = [...messages][0];
+
+    var loc = msg.querySelector(".message-location");
+    ok(loc, "location element exists");
+    is(loc.textContent.trim(), sw.Scratchpad.uniqueName + ":1",
+        "location value is correct");
+
+    sw.addEventListener("focus", function onFocus() {
+      sw.removeEventListener("focus", onFocus, true);
+
+      let win = Services.wm.getMostRecentWindow("devtools:scratchpad");
+
+      ok(win, "there are active Scratchpad windows");
+      is(win.Scratchpad.uniqueName, sw.Scratchpad.uniqueName,
+          "correct window is in focus");
+
+      // gScratchpadWindow will be closed automatically but we need to
+      // close the second window ourselves.
+      sw.close();
+      finish();
+    }, true);
+
+    // Simulate a click on the "Scratchpad/N:1" link.
+    EventUtils.synthesizeMouse(loc, 2, 2, {}, hud.iframeWindow);
+  }
+
+  // Sending messages to web console is an asynchronous operation. That's
+  // why we have to setup an observer here.
+  hud.ui.once("messages-added", onMessage);
+
+  sp.setText("console.log('foo');");
+  sp.run().then(function ([selection, error, result]) {
+    is(selection, "console.log('foo');", "selection is correct");
+    is(error, undefined, "error is correct");
+    is(result.type, "undefined", "result is correct");
+  });
+}