diff --git a/dom/base/nsGkAtomList.h b/dom/base/nsGkAtomList.h
index e4ae7ede81..aa4ef2ca39 100644
--- a/dom/base/nsGkAtomList.h
+++ b/dom/base/nsGkAtomList.h
@@ -704,6 +704,7 @@ GK_ATOM(onattributechanged, "onattributechanged")
 GK_ATOM(onattributereadreq, "onattributereadreq")
 GK_ATOM(onattributewritereq, "onattributewritereq")
 GK_ATOM(onaudioprocess, "onaudioprocess")
+GK_ATOM(onauxclick, "onauxclick")
 GK_ATOM(onbeforecopy, "onbeforecopy")
 GK_ATOM(onbeforecut, "onbeforecut")
 GK_ATOM(onbeforepaste, "onbeforepaste")
diff --git a/dom/events/EventNameList.h b/dom/events/EventNameList.h
index ba2427623e..891035c43e 100644
--- a/dom/events/EventNameList.h
+++ b/dom/events/EventNameList.h
@@ -164,6 +164,10 @@ EVENT(change,
       eFormChange,
       EventNameType_HTMLXUL,
       eBasicEventClass)
+EVENT(auxclick,
+      eMouseAuxClick,
+      EventNameType_All,
+      eMouseEventClass)
 EVENT(click,
       eMouseClick,
       EventNameType_All,
diff --git a/dom/events/EventStateManager.cpp b/dom/events/EventStateManager.cpp
index c6b304183b..7bbfe21b79 100644
--- a/dom/events/EventStateManager.cpp
+++ b/dom/events/EventStateManager.cpp
@@ -492,6 +492,7 @@ IsMessageMouseUserActivity(EventMessage aMessage)
   return aMessage == eMouseMove ||
          aMessage == eMouseUp ||
          aMessage == eMouseDown ||
+         aMessage == eMouseAuxClick ||
          aMessage == eMouseDoubleClick ||
          aMessage == eMouseClick ||
          aMessage == eMouseActivate ||
@@ -4632,6 +4633,32 @@ EventStateManager::SetClickCount(WidgetMouseEvent* aEvent,
   return NS_OK;
 }
 
+nsresult
+EventStateManager::InitAndDispatchClickEvent(WidgetMouseEvent* aEvent,
+                                             nsEventStatus* aStatus,
+                                             EventMessage aMessage,
+                                             nsIPresShell* aPresShell,
+                                             nsIContent* aMouseTarget,
+                                             nsWeakFrame aCurrentTarget,
+                                             bool aNoContentDispatch)
+{
+  WidgetMouseEvent event(aEvent->IsTrusted(), aMessage,
+                         aEvent->mWidget, WidgetMouseEvent::eReal);
+
+  event.mRefPoint = aEvent->mRefPoint;
+  event.mClickCount = aEvent->mClickCount;
+  event.mModifiers = aEvent->mModifiers;
+  event.buttons = aEvent->buttons;
+  event.mTime = aEvent->mTime;
+  event.mTimeStamp = aEvent->mTimeStamp;
+  event.mFlags.mNoContentDispatch = aNoContentDispatch;
+  event.button = aEvent->button;
+  event.inputSource = aEvent->inputSource;
+
+  return aPresShell->HandleEventWithTarget(&event, aCurrentTarget,
+                                           aMouseTarget, aStatus);
+}
+
 nsresult
 EventStateManager::CheckForAndDispatchClick(WidgetMouseEvent* aEvent,
                                             nsEventStatus* aStatus)
@@ -4651,17 +4678,7 @@ EventStateManager::CheckForAndDispatchClick(WidgetMouseEvent* aEvent,
      (aEvent->button == WidgetMouseEvent::eMiddleButton ||
       aEvent->button == WidgetMouseEvent::eRightButton);
 
-    WidgetMouseEvent event(aEvent->IsTrusted(), eMouseClick,
-                           aEvent->mWidget, WidgetMouseEvent::eReal);
-    event.mRefPoint = aEvent->mRefPoint;
-    event.mClickCount = aEvent->mClickCount;
-    event.mModifiers = aEvent->mModifiers;
-    event.buttons = aEvent->buttons;
-    event.mTime = aEvent->mTime;
-    event.mTimeStamp = aEvent->mTimeStamp;
-    event.mFlags.mNoContentDispatch = notDispatchToContents;
-    event.button = aEvent->button;
-    event.inputSource = aEvent->inputSource;
+    bool fireAuxClick = notDispatchToContents;
 
     nsCOMPtr<nsIPresShell> presShell = mPresContext->GetPresShell();
     if (presShell) {
@@ -4680,23 +4697,22 @@ EventStateManager::CheckForAndDispatchClick(WidgetMouseEvent* aEvent,
 
       // HandleEvent clears out mCurrentTarget which we might need again
       nsWeakFrame currentTarget = mCurrentTarget;
-      ret = presShell->HandleEventWithTarget(&event, currentTarget,
-                                             mouseContent, aStatus);
+      ret = InitAndDispatchClickEvent(aEvent, aStatus, eMouseClick,
+                                      presShell, mouseContent, currentTarget,
+                                      notDispatchToContents);
+
       if (NS_SUCCEEDED(ret) && aEvent->mClickCount == 2 &&
           mouseContent && mouseContent->IsInComposedDoc()) {
         //fire double click
-        WidgetMouseEvent event2(aEvent->IsTrusted(), eMouseDoubleClick,
-                                aEvent->mWidget, WidgetMouseEvent::eReal);
-        event2.mRefPoint = aEvent->mRefPoint;
-        event2.mClickCount = aEvent->mClickCount;
-        event2.mModifiers = aEvent->mModifiers;
-        event2.buttons = aEvent->buttons;
-        event2.mFlags.mNoContentDispatch = notDispatchToContents;
-        event2.button = aEvent->button;
-        event2.inputSource = aEvent->inputSource;
-
-        ret = presShell->HandleEventWithTarget(&event2, currentTarget,
-                                               mouseContent, aStatus);
+        ret = InitAndDispatchClickEvent(aEvent, aStatus, eMouseDoubleClick,
+                                        presShell, mouseContent, currentTarget,
+                                        notDispatchToContents);
+      }
+      if (NS_SUCCEEDED(ret) && mouseContent && fireAuxClick &&
+          mouseContent->IsInComposedDoc()) {
+        ret = InitAndDispatchClickEvent(aEvent, aStatus, eMouseAuxClick,
+                                        presShell, mouseContent, currentTarget,
+                                        false);
       }
     }
   }
diff --git a/dom/events/EventStateManager.h b/dom/events/EventStateManager.h
index 49ecf05865..d0461e7fae 100644
--- a/dom/events/EventStateManager.h
+++ b/dom/events/EventStateManager.h
@@ -415,6 +415,13 @@ protected:
    */
   void UpdateDragDataTransfer(WidgetDragEvent* dragEvent);
 
+  static nsresult InitAndDispatchClickEvent(WidgetMouseEvent* aEvent,
+                                            nsEventStatus* aStatus,
+                                            EventMessage aMessage,
+                                            nsIPresShell* aPresShell,
+                                            nsIContent* aMouseTarget,
+                                            nsWeakFrame aCurrentTarget,
+                                            bool aNoContentDispatch);
   nsresult SetClickCount(WidgetMouseEvent* aEvent, nsEventStatus* aStatus);
   nsresult CheckForAndDispatchClick(WidgetMouseEvent* aEvent,
                                     nsEventStatus* aStatus);
@@ -1046,6 +1053,7 @@ private:
 #define NS_EVENT_NEEDS_FRAME(event) \
     (!(event)->HasPluginActivationEventMessage() && \
      (event)->mMessage != eMouseClick && \
-     (event)->mMessage != eMouseDoubleClick)
+     (event)->mMessage != eMouseDoubleClick && \
+     (event)->mMessage != eMouseAuxClick)
 
 #endif // mozilla_EventStateManager_h_
diff --git a/dom/events/WheelHandlingHelper.cpp b/dom/events/WheelHandlingHelper.cpp
index 7665ee9225..81f2b6bfab 100644
--- a/dom/events/WheelHandlingHelper.cpp
+++ b/dom/events/WheelHandlingHelper.cpp
@@ -257,6 +257,7 @@ WheelTransaction::OnEvent(WidgetEvent* aEvent)
     case eMouseUp:
     case eMouseDown:
     case eMouseDoubleClick:
+    case eMouseAuxClick:
     case eMouseClick:
     case eContextMenu:
     case eDrop:
diff --git a/dom/events/test/mochitest.ini b/dom/events/test/mochitest.ini
index e100e60a18..0397487bb8 100644
--- a/dom/events/test/mochitest.ini
+++ b/dom/events/test/mochitest.ini
@@ -184,3 +184,4 @@ skip-if = toolkit == 'android' #CRASH_DUMP, RANDOM
 [test_wheel_default_action.html]
 [test_bug687787.html]
 [test_bug1298970.html]
+[test_bug1304044.html]
diff --git a/dom/events/test/test_bug1304044.html b/dom/events/test/test_bug1304044.html
new file mode 100644
index 0000000000..0911dcf737
--- /dev/null
+++ b/dom/events/test/test_bug1304044.html
@@ -0,0 +1,133 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1304044
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 1304044</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+  <script type="application/javascript">
+    var eventsFired = [];
+    var target;
+    var eventsExpected;
+
+    function GetNodeString(node) {
+      if (node == window)
+        return "window";
+      if (node == document)
+        return "document";
+      if (node.id)
+        return node.id;
+      if (node.nodeName)
+        return node.nodeName;
+      return node;
+    }
+
+    function TargetAndListener(listener, target) {
+      this.listener = listener;
+      this.target = target;
+    }
+
+    TargetAndListener.prototype.toString = function() {
+      var targetName = GetNodeString(this.target);
+      var listenerName = GetNodeString(this.listener);
+      return "(listener: " + listenerName + ", target: " + targetName + ")";
+    }
+
+    var tests = [
+      TestAuxClickBubblesForEventListener,
+      TestAuxClickBubblesForOnAuxClick,
+    ];
+
+    function CompareEvents(evt, expected) {
+      return evt && expected && evt.listener == expected.listener &&
+          evt.target == expected.target;
+    }
+
+    function ResetEventsFired() {
+      eventsFired = [];
+    }
+
+    function ClearEventListeners() {
+      for (i in arguments) {
+        arguments[i].removeEventListener("auxclick", log_event);
+      }
+    }
+
+    function ClickTarget(tgt) {
+      synthesizeMouseAtCenter(tgt, {type : "mousedown", button: 2}, window);
+      synthesizeMouseAtCenter(tgt, {type : "mouseup", button: 2}, window);
+    }
+
+    function log_event(e) {
+      eventsFired[eventsFired.length] = new TargetAndListener(this, e.target);
+    }
+
+    function CompareEventsToExpected(expected, actual) {
+      for (var i = 0; i < expected.length || i < actual.length; i++) {
+        ok(CompareEvents(actual[i], expected[i]),
+           "Auxclick receiver's don't match: TargetAndListener " +
+           i + ": Expected: " + expected[i] + ", Actual: " + actual[i]);
+      }
+    }
+
+    function TestAuxClickBubblesForEventListener() {
+      target.addEventListener("auxclick", log_event);
+      document.addEventListener("auxclick", log_event);
+      window.addEventListener("auxclick", log_event);
+
+      ClickTarget(target)
+      CompareEventsToExpected(eventsExpected, eventsFired);
+      ResetEventsFired();
+      ClearEventListeners(target, document, window);
+    }
+
+    function TestAuxClickBubblesForOnAuxClick() {
+      target.onauxclick = log_event;
+      document.onauxclick = log_event;
+      window.onauxclick = log_event;
+
+      ClickTarget(target);
+      CompareEventsToExpected(eventsExpected, eventsFired);
+      ResetEventsFired();
+    }
+
+    function RunTests(){
+      for (var i = 0; i < tests.length; i++) {
+        tests[i]();
+      }
+    }
+
+    function Begin() {
+      target = document.getElementById("target");
+      eventsExpected =  [
+        new TargetAndListener(target, target),
+        new TargetAndListener(document, target),
+        new TargetAndListener(window, target),
+      ];
+      RunTests();
+      target.remove();
+      SimpleTest.finish();
+    }
+
+    window.onload = function() {
+      SimpleTest.waitForExplicitFinish();
+      SimpleTest.executeSoon(Begin);
+    }
+  </script>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1304044">Mozilla Bug 1304044</a>
+<p id="display">
+  <div id="target">Target</div>
+</p>
+<div id="content" style:"display:none">
+
+</div>
+<pre id="test">
+</pre>
+</body>
+</html>
diff --git a/dom/plugins/base/nsPluginInstanceOwner.cpp b/dom/plugins/base/nsPluginInstanceOwner.cpp
index b7651be1ad..291ae576dc 100644
--- a/dom/plugins/base/nsPluginInstanceOwner.cpp
+++ b/dom/plugins/base/nsPluginInstanceOwner.cpp
@@ -2532,6 +2532,7 @@ nsEventStatus nsPluginInstanceOwner::ProcessEvent(const WidgetGUIEvent& anEvent)
       NS_ASSERTION(anEvent.mMessage == eMouseDown ||
                    anEvent.mMessage == eMouseUp ||
                    anEvent.mMessage == eMouseDoubleClick ||
+                   anEvent.mMessage == eMouseAuxClick ||
                    anEvent.mMessage == eMouseOver ||
                    anEvent.mMessage == eMouseOut ||
                    anEvent.mMessage == eMouseMove ||
@@ -2594,6 +2595,7 @@ nsEventStatus nsPluginInstanceOwner::ProcessEvent(const WidgetGUIEvent& anEvent)
         switch (anEvent.mMessage) {
           case eMouseClick:
           case eMouseDoubleClick:
+          case eMouseAuxClick:
             // Button up/down events sent instead.
             return rv;
           default:
@@ -2797,6 +2799,7 @@ nsEventStatus nsPluginInstanceOwner::ProcessEvent(const WidgetGUIEvent& anEvent)
         switch (anEvent.mMessage) {
           case eMouseClick:
           case eMouseDoubleClick:
+          case eMouseAuxClick:
             // Button up/down events sent instead.
             return rv;
           default:
diff --git a/dom/webidl/EventHandler.webidl b/dom/webidl/EventHandler.webidl
index e65a757873..fce6d9b52c 100644
--- a/dom/webidl/EventHandler.webidl
+++ b/dom/webidl/EventHandler.webidl
@@ -33,6 +33,7 @@ interface GlobalEventHandlers {
 //         attribute OnErrorEventHandler onerror;
            attribute EventHandler onfocus;
            //(Not implemented)attribute EventHandler oncancel;
+           attribute EventHandler onauxclick;
            attribute EventHandler oncanplay;
            attribute EventHandler oncanplaythrough;
            attribute EventHandler onchange;
diff --git a/gfx/layers/apz/src/APZCTreeManager.cpp b/gfx/layers/apz/src/APZCTreeManager.cpp
index 857ae59582..f543263602 100644
--- a/gfx/layers/apz/src/APZCTreeManager.cpp
+++ b/gfx/layers/apz/src/APZCTreeManager.cpp
@@ -1145,6 +1145,7 @@ APZCTreeManager::UpdateWheelTransaction(LayoutDeviceIntPoint aRefPoint,
    case eMouseUp:
    case eMouseDown:
    case eMouseDoubleClick:
+   case eMouseAuxClick:
    case eMouseClick:
    case eContextMenu:
    case eDrop:
diff --git a/widget/BasicEvents.h b/widget/BasicEvents.h
index da8d819ef4..a6228f179f 100644
--- a/widget/BasicEvents.h
+++ b/widget/BasicEvents.h
@@ -585,6 +585,7 @@ public:
       case eMouseEventClass:
         mFlags.mComposed = mMessage == eMouseClick ||
                            mMessage == eMouseDoubleClick ||
+                           mMessage == eMouseAuxClick ||
                            mMessage == eMouseDown || mMessage == eMouseUp ||
                            mMessage == eMouseEnter || mMessage == eMouseLeave ||
                            mMessage == eMouseOver || mMessage == eMouseOut ||
diff --git a/widget/EventMessageList.h b/widget/EventMessageList.h
index 7fe642637e..f6cf76209b 100644
--- a/widget/EventMessageList.h
+++ b/widget/EventMessageList.h
@@ -84,6 +84,7 @@ NS_EVENT_MESSAGE(eMouseEnterIntoWidget)
 NS_EVENT_MESSAGE(eMouseExitFromWidget)
 NS_EVENT_MESSAGE(eMouseDoubleClick)
 NS_EVENT_MESSAGE(eMouseClick)
+NS_EVENT_MESSAGE(eMouseAuxClick)
 // eMouseActivate is fired when the widget is activated by a click.
 NS_EVENT_MESSAGE(eMouseActivate)
 NS_EVENT_MESSAGE(eMouseOver)
diff --git a/widget/WidgetEventImpl.cpp b/widget/WidgetEventImpl.cpp
index 52e2b9b40e..7dd292cb0d 100644
--- a/widget/WidgetEventImpl.cpp
+++ b/widget/WidgetEventImpl.cpp
@@ -236,6 +236,7 @@ WidgetEvent::HasMouseEventMessage() const
     case eMouseUp:
     case eMouseClick:
     case eMouseDoubleClick:
+    case eMouseAuxClick:
     case eMouseEnterIntoWidget:
     case eMouseExitFromWidget:
     case eMouseActivate:
diff --git a/widget/nsBaseWidget.cpp b/widget/nsBaseWidget.cpp
index b820fed3cc..909660f715 100644
--- a/widget/nsBaseWidget.cpp
+++ b/widget/nsBaseWidget.cpp
@@ -3086,6 +3086,7 @@ case _value: eventName.AssignLiteral(_name) ; break
     _ASSIGN_eventName(eMouseDown,"eMouseDown");
     _ASSIGN_eventName(eMouseUp,"eMouseUp");
     _ASSIGN_eventName(eMouseClick,"eMouseClick");
+    _ASSIGN_eventName(eMouseAuxClick,"eMouseAuxClick");
     _ASSIGN_eventName(eMouseDoubleClick,"eMouseDoubleClick");
     _ASSIGN_eventName(eMouseMove,"eMouseMove");
     _ASSIGN_eventName(eLoad,"eLoad");
diff --git a/widget/windows/WinUtils.cpp b/widget/windows/WinUtils.cpp
index 149513b2fa..3ff46513ee 100644
--- a/widget/windows/WinUtils.cpp
+++ b/widget/windows/WinUtils.cpp
@@ -1140,7 +1140,8 @@ WinUtils::GetIsMouseFromTouch(EventMessage aEventMessage)
   const uint32_t MOZ_T_I_SIGNATURE = TABLET_INK_TOUCH | TABLET_INK_SIGNATURE;
   const uint32_t MOZ_T_I_CHECK_TCH = TABLET_INK_TOUCH | TABLET_INK_CHECK;
   return ((aEventMessage == eMouseMove || aEventMessage == eMouseDown ||
-           aEventMessage == eMouseUp || aEventMessage == eMouseDoubleClick) &&
+           aEventMessage == eMouseUp || aEventMessage == eMouseAuxClick ||
+           aEventMessage == eMouseDoubleClick) &&
          (GetMessageExtraInfo() & MOZ_T_I_SIGNATURE) == MOZ_T_I_CHECK_TCH);
 }