diff --git a/addon-sdk/source/test/addons/private-browsing-supported/sidebar/utils.js b/addon-sdk/source/test/addons/private-browsing-supported/sidebar/utils.js
index 5fbe18ba48e2..6154719457fc 100644
--- a/addon-sdk/source/test/addons/private-browsing-supported/sidebar/utils.js
+++ b/addon-sdk/source/test/addons/private-browsing-supported/sidebar/utils.js
@@ -44,7 +44,7 @@ function simulateCommand(ele) {
   let { document } = window;
   var evt = document.createEvent('XULCommandEvent');
   evt.initCommandEvent('command', true, true, window,
-    0, false, false, false, false, null);
+    0, false, false, false, false, null, 0);
   ele.dispatchEvent(evt);
 }
 exports.simulateCommand = simulateCommand;
diff --git a/addon-sdk/source/test/sidebar/utils.js b/addon-sdk/source/test/sidebar/utils.js
index 4b3a26417155..ffe7b9c7e2d7 100644
--- a/addon-sdk/source/test/sidebar/utils.js
+++ b/addon-sdk/source/test/sidebar/utils.js
@@ -51,7 +51,7 @@ function simulateCommand(ele) {
   let { document } = window;
   var evt = document.createEvent('XULCommandEvent');
   evt.initCommandEvent('command', true, true, window,
-    0, false, false, false, false, null);
+    0, false, false, false, false, null, 0);
   ele.dispatchEvent(evt);
 }
 exports.simulateCommand = simulateCommand;
diff --git a/browser/base/content/browser-gestureSupport.js b/browser/base/content/browser-gestureSupport.js
index 01577e202254..4f0c7b0ee54b 100644
--- a/browser/base/content/browser-gestureSupport.js
+++ b/browser/base/content/browser-gestureSupport.js
@@ -334,7 +334,8 @@ var gGestureSupport = {
         let cmdEvent = document.createEvent("xulcommandevent");
         cmdEvent.initCommandEvent("command", true, true, window, 0,
                                   aEvent.ctrlKey, aEvent.altKey,
-                                  aEvent.shiftKey, aEvent.metaKey, aEvent);
+                                  aEvent.shiftKey, aEvent.metaKey,
+                                  aEvent, aEvent.mozInputSource);
         node.dispatchEvent(cmdEvent);
       }
 
diff --git a/browser/base/content/browser.js b/browser/base/content/browser.js
index 28be8c1eb2c8..8b4b8abe8743 100755
--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -380,7 +380,7 @@ const gClickAndHoldListenersOnElement = {
       let cmdEvent = document.createEvent("xulcommandevent");
       cmdEvent.initCommandEvent("command", true, true, window, 0,
                                 aEvent.ctrlKey, aEvent.altKey, aEvent.shiftKey,
-                                aEvent.metaKey, null);
+                                aEvent.metaKey, null, aEvent.mozInputSource);
       aEvent.currentTarget.dispatchEvent(cmdEvent);
 
       // This is here to cancel the XUL default event
diff --git a/browser/components/customizableui/CustomizableWidgets.jsm b/browser/components/customizableui/CustomizableWidgets.jsm
index 9035ad806ef5..263c40e3ad4f 100644
--- a/browser/components/customizableui/CustomizableWidgets.jsm
+++ b/browser/components/customizableui/CustomizableWidgets.jsm
@@ -133,7 +133,7 @@ function fillSubviewFromMenuItems(aMenuItems, aSubview) {
           newEvent.initCommandEvent(
             event.type, event.bubbles, event.cancelable, event.view,
             event.detail, event.ctrlKey, event.altKey, event.shiftKey,
-            event.metaKey, event.sourceEvent);
+            event.metaKey, event.sourceEvent, 0);
           item.dispatchEvent(newEvent);
         });
       }
diff --git a/browser/components/preferences/in-content-new/tests/browser_applications_selection.js b/browser/components/preferences/in-content-new/tests/browser_applications_selection.js
index 325517da5a36..67d8cec75c73 100644
--- a/browser/components/preferences/in-content-new/tests/browser_applications_selection.js
+++ b/browser/components/preferences/in-content-new/tests/browser_applications_selection.js
@@ -38,7 +38,7 @@ add_task(async function selectInternalOptionForFeed() {
 
   // Select the option.
   let cmdEvent = win.document.createEvent("xulcommandevent");
-  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null);
+  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null, 0);
   chooseItems[0].dispatchEvent(cmdEvent);
 
   // Check that we display the correct result.
diff --git a/browser/components/preferences/in-content-new/tests/browser_change_app_handler.js b/browser/components/preferences/in-content-new/tests/browser_change_app_handler.js
index f4eddba1c9fc..fe969f8a6a02 100644
--- a/browser/components/preferences/in-content-new/tests/browser_change_app_handler.js
+++ b/browser/components/preferences/in-content-new/tests/browser_change_app_handler.js
@@ -34,7 +34,7 @@ add_task(async function() {
   let chooseItem = list.firstChild.querySelector(".choose-app-item");
   let dialogLoadedPromise = promiseLoadSubDialog("chrome://global/content/appPicker.xul");
   let cmdEvent = win.document.createEvent("xulcommandevent");
-  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null);
+  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null, 0);
   chooseItem.dispatchEvent(cmdEvent);
 
   let dialog = await dialogLoadedPromise;
@@ -63,7 +63,7 @@ add_task(async function() {
 
   let manageItem = list.firstChild.querySelector(".manage-app-item");
   cmdEvent = win.document.createEvent("xulcommandevent");
-  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null);
+  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null, 0);
   manageItem.dispatchEvent(cmdEvent);
 
   dialog = await dialogLoadedPromise;
diff --git a/browser/components/preferences/in-content/tests/browser_applications_selection.js b/browser/components/preferences/in-content/tests/browser_applications_selection.js
index 9b7503c98d12..9c7aa20f7bd9 100644
--- a/browser/components/preferences/in-content/tests/browser_applications_selection.js
+++ b/browser/components/preferences/in-content/tests/browser_applications_selection.js
@@ -38,7 +38,7 @@ add_task(async function selectInternalOptionForFeed() {
 
   // Select the option.
   let cmdEvent = win.document.createEvent("xulcommandevent");
-  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null);
+  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null, 0);
   chooseItems[0].dispatchEvent(cmdEvent);
 
   // Check that we display the correct result.
diff --git a/browser/components/preferences/in-content/tests/browser_change_app_handler.js b/browser/components/preferences/in-content/tests/browser_change_app_handler.js
index dd9081073f1a..3adae269e1ae 100644
--- a/browser/components/preferences/in-content/tests/browser_change_app_handler.js
+++ b/browser/components/preferences/in-content/tests/browser_change_app_handler.js
@@ -33,7 +33,7 @@ add_task(async function() {
   let chooseItem = list.firstChild.querySelector(".choose-app-item");
   let dialogLoadedPromise = promiseLoadSubDialog("chrome://global/content/appPicker.xul");
   let cmdEvent = win.document.createEvent("xulcommandevent");
-  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null);
+  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null, 0);
   chooseItem.dispatchEvent(cmdEvent);
 
   let dialog = await dialogLoadedPromise;
@@ -62,7 +62,7 @@ add_task(async function() {
 
   let manageItem = list.firstChild.querySelector(".manage-app-item");
   cmdEvent = win.document.createEvent("xulcommandevent");
-  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null);
+  cmdEvent.initCommandEvent("command", true, true, win, 0, false, false, false, false, null, 0);
   manageItem.dispatchEvent(cmdEvent);
 
   dialog = await dialogLoadedPromise;
diff --git a/devtools/client/performance/test/helpers/input-utils.js b/devtools/client/performance/test/helpers/input-utils.js
index 180091d076aa..ce109ac38fe2 100644
--- a/devtools/client/performance/test/helpers/input-utils.js
+++ b/devtools/client/performance/test/helpers/input-utils.js
@@ -11,7 +11,7 @@ exports.VERTICAL_AXIS = 2;
 exports.command = (node) => {
   let ev = node.ownerDocument.createEvent("XULCommandEvent");
   ev.initCommandEvent("command", true, true, node.ownerDocument.defaultView, 0, false,
-                      false, false, false, null);
+                      false, false, false, null, 0);
   node.dispatchEvent(ev);
 };
 
diff --git a/devtools/client/webaudioeditor/test/head.js b/devtools/client/webaudioeditor/test/head.js
index 098c1e000c38..56b67b2a70f6 100644
--- a/devtools/client/webaudioeditor/test/head.js
+++ b/devtools/client/webaudioeditor/test/head.js
@@ -363,7 +363,7 @@ function mouseOver(win, element) {
 
 function command(button) {
   let ev = button.ownerDocument.createEvent("XULCommandEvent");
-  ev.initCommandEvent("command", true, true, button.ownerDocument.defaultView, 0, false, false, false, false, null);
+  ev.initCommandEvent("command", true, true, button.ownerDocument.defaultView, 0, false, false, false, false, null, 0);
   button.dispatchEvent(ev);
 }
 
diff --git a/devtools/client/webconsole/test/browser_webconsole_bug_601667_filter_buttons.js b/devtools/client/webconsole/test/browser_webconsole_bug_601667_filter_buttons.js
index 6dae0a7b7ea3..6823e3ce7f35 100644
--- a/devtools/client/webconsole/test/browser_webconsole_bug_601667_filter_buttons.js
+++ b/devtools/client/webconsole/test/browser_webconsole_bug_601667_filter_buttons.js
@@ -258,7 +258,7 @@ function altClickButton(node) {
 function chooseMenuItem(node) {
   let event = document.createEvent("XULCommandEvent");
   event.initCommandEvent("command", true, true, window, 0, false, false, false,
-                         false, null);
+                         false, null, 0);
   node.dispatchEvent(event);
 }
 
diff --git a/dom/base/nsContentUtils.cpp b/dom/base/nsContentUtils.cpp
index 13a0bc588fe2..7a903e9cd9ce 100644
--- a/dom/base/nsContentUtils.cpp
+++ b/dom/base/nsContentUtils.cpp
@@ -6617,7 +6617,8 @@ nsContentUtils::DispatchXULCommand(nsIContent* aTarget,
                                    bool aCtrl,
                                    bool aAlt,
                                    bool aShift,
-                                   bool aMeta)
+                                   bool aMeta,
+                                   uint16_t aInputSource)
 {
   NS_ENSURE_STATE(aTarget);
   nsIDocument* doc = aTarget->OwnerDoc();
@@ -6630,7 +6631,7 @@ nsContentUtils::DispatchXULCommand(nsIContent* aTarget,
                                                            nullptr);
   xulCommand->InitCommandEvent(NS_LITERAL_STRING("command"), true, true,
                                doc->GetInnerWindow(), 0, aCtrl, aAlt, aShift,
-                               aMeta, aSourceEvent);
+                               aMeta, aSourceEvent, aInputSource);
 
   if (aShell) {
     nsEventStatus status = nsEventStatus_eIgnore;
diff --git a/dom/base/nsContentUtils.h b/dom/base/nsContentUtils.h
index 4b0d862385d4..029ebe804f1e 100644
--- a/dom/base/nsContentUtils.h
+++ b/dom/base/nsContentUtils.h
@@ -39,6 +39,7 @@
 #include "mozilla/Maybe.h"
 #include "nsIContentPolicy.h"
 #include "nsIDocument.h"
+#include "nsIDOMMouseEvent.h"
 #include "nsPIDOMWindow.h"
 #include "nsRFPService.h"
 
@@ -1994,7 +1995,8 @@ public:
                                      bool aCtrl = false,
                                      bool aAlt = false,
                                      bool aShift = false,
-                                     bool aMeta = false);
+                                     bool aMeta = false,
+                                     uint16_t inputSource = nsIDOMMouseEvent::MOZ_SOURCE_UNKNOWN);
 
   static bool CheckMayLoad(nsIPrincipal* aPrincipal, nsIChannel* aChannel, bool aAllowIfInheritsPrincipal);
 
diff --git a/dom/events/XULCommandEvent.cpp b/dom/events/XULCommandEvent.cpp
index 5084588b47c3..ba9337fcfe4b 100644
--- a/dom/events/XULCommandEvent.cpp
+++ b/dom/events/XULCommandEvent.cpp
@@ -92,6 +92,20 @@ XULCommandEvent::GetMetaKey(bool* aIsDown)
   return NS_OK;
 }
 
+uint16_t
+XULCommandEvent::InputSource()
+{
+  return mInputSource;
+}
+
+NS_IMETHODIMP
+XULCommandEvent::GetInputSource(uint16_t* aInputSource)
+{
+  NS_ENSURE_ARG_POINTER(aInputSource);
+  *aInputSource = InputSource();
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 XULCommandEvent::GetSourceEvent(nsIDOMEvent** aSourceEvent)
 {
@@ -111,7 +125,8 @@ XULCommandEvent::InitCommandEvent(const nsAString& aType,
                                   bool aAltKey,
                                   bool aShiftKey,
                                   bool aMetaKey,
-                                  nsIDOMEvent* aSourceEvent)
+                                  nsIDOMEvent* aSourceEvent,
+                                  uint16_t aInputSource)
 {
   NS_ENSURE_TRUE(!mEvent->mFlags.mIsBeingDispatched, NS_OK);
 
@@ -121,6 +136,7 @@ XULCommandEvent::InitCommandEvent(const nsAString& aType,
   mEvent->AsInputEvent()->InitBasicModifiers(aCtrlKey, aAltKey,
                                              aShiftKey, aMetaKey);
   mSourceEvent = aSourceEvent;
+  mInputSource = aInputSource;
 
   return NS_OK;
 }
diff --git a/dom/events/XULCommandEvent.h b/dom/events/XULCommandEvent.h
index ea5e85a75fe1..083f72c9182a 100644
--- a/dom/events/XULCommandEvent.h
+++ b/dom/events/XULCommandEvent.h
@@ -40,6 +40,7 @@ public:
   bool CtrlKey();
   bool ShiftKey();
   bool MetaKey();
+  uint16_t InputSource();
 
   already_AddRefed<Event> GetSourceEvent()
   {
@@ -54,17 +55,19 @@ public:
                         int32_t aDetail,
                         bool aCtrlKey, bool aAltKey,
                         bool aShiftKey, bool aMetaKey,
-                        Event* aSourceEvent)
+                        Event* aSourceEvent,
+                        uint16_t aInputSource)
   {
     InitCommandEvent(aType, aCanBubble, aCancelable, aView->AsInner(),
                      aDetail, aCtrlKey, aAltKey, aShiftKey, aMetaKey,
-                     aSourceEvent);
+                     aSourceEvent, aInputSource);
   }
 
 protected:
   ~XULCommandEvent() {}
 
   nsCOMPtr<nsIDOMEvent> mSourceEvent;
+  uint16_t mInputSource;
 };
 
 } // namespace dom
diff --git a/dom/interfaces/xul/nsIDOMXULCommandEvent.idl b/dom/interfaces/xul/nsIDOMXULCommandEvent.idl
index c32a9e47d3f3..320f3633e410 100644
--- a/dom/interfaces/xul/nsIDOMXULCommandEvent.idl
+++ b/dom/interfaces/xul/nsIDOMXULCommandEvent.idl
@@ -23,6 +23,11 @@ interface nsIDOMXULCommandEvent : nsIDOMUIEvent
   readonly attribute boolean altKey;
   readonly attribute boolean metaKey;
 
+  /**
+   * The input source, if this event was triggered by a mouse event.
+  */
+  readonly attribute unsigned short inputSource;
+
   /**
    * If the command event was redispatched because of a command= attribute
    * on the original target, sourceEvent will be set to the original DOM Event.
@@ -42,5 +47,6 @@ interface nsIDOMXULCommandEvent : nsIDOMUIEvent
                         in boolean altKeyArg,
                         in boolean shiftKeyArg,
                         in boolean metaKeyArg,
-                        in nsIDOMEvent sourceEvent);
+                        in nsIDOMEvent sourceEvent,
+                        in unsigned short inputSource);
 };
diff --git a/dom/webidl/XULCommandEvent.webidl b/dom/webidl/XULCommandEvent.webidl
index 72dc3802ee86..a652a4f2b1c2 100644
--- a/dom/webidl/XULCommandEvent.webidl
+++ b/dom/webidl/XULCommandEvent.webidl
@@ -12,6 +12,8 @@ interface XULCommandEvent : UIEvent
   readonly attribute boolean altKey;
   readonly attribute boolean metaKey;
 
+  readonly attribute unsigned short inputSource;
+
   readonly attribute Event? sourceEvent;
 
   void initCommandEvent(DOMString type,
@@ -23,5 +25,6 @@ interface XULCommandEvent : UIEvent
                         optional boolean altKey = false,
                         optional boolean shiftKey = false,
                         optional boolean metaKey = false,
-                        optional Event? sourceEvent = null);
+                        optional Event? sourceEvent = null,
+                        optional unsigned short inputSource = 0);
 };
diff --git a/dom/xul/nsXULElement.cpp b/dom/xul/nsXULElement.cpp
index 36d97a9d2872..88a6fd4f55f6 100644
--- a/dom/xul/nsXULElement.cpp
+++ b/dom/xul/nsXULElement.cpp
@@ -1255,6 +1255,7 @@ nsXULElement::DispatchXULCommand(const EventChainVisitor& aVisitor,
         // sourceEvent will be the original command event that we're
         // handling.
         nsCOMPtr<nsIDOMEvent> domEvent = aVisitor.mDOMEvent;
+        uint16_t inputSource = nsIDOMMouseEvent::MOZ_SOURCE_UNKNOWN;
         while (domEvent) {
             Event* event = domEvent->InternalDOMEvent();
             NS_ENSURE_STATE(!SameCOMIdentity(event->GetOriginalTarget(),
@@ -1263,6 +1264,7 @@ nsXULElement::DispatchXULCommand(const EventChainVisitor& aVisitor,
                 do_QueryInterface(domEvent);
             if (commandEvent) {
                 commandEvent->GetSourceEvent(getter_AddRefs(domEvent));
+                commandEvent->GetInputSource(&inputSource);
             } else {
                 domEvent = nullptr;
             }
@@ -1276,7 +1278,8 @@ nsXULElement::DispatchXULCommand(const EventChainVisitor& aVisitor,
           orig->IsControl(),
           orig->IsAlt(),
           orig->IsShift(),
-          orig->IsMeta());
+          orig->IsMeta(),
+          inputSource);
     } else {
         NS_WARNING("A XUL element is attached to a command that doesn't exist!\n");
     }
diff --git a/dom/xul/test/test_bug1290965.xul b/dom/xul/test/test_bug1290965.xul
index 8701b55be5e5..613a4a2e4a60 100644
--- a/dom/xul/test/test_bug1290965.xul
+++ b/dom/xul/test/test_bug1290965.xul
@@ -17,7 +17,7 @@
       let cmdEvent = document.createEvent("xulcommandevent");
       cmdEvent.initCommandEvent("command", true, true, window, 0,
                                 aEvent.ctrlKey, aEvent.altKey, aEvent.shiftKey,
-                                aEvent.metaKey, null);
+                                aEvent.metaKey, null, aEvent.mozInputSource);
       aEvent.currentTarget.dispatchEvent(cmdEvent);
     });
 
@@ -25,7 +25,7 @@
       let cmdEvent = document.createEvent("xulcommandevent");
       cmdEvent.initCommandEvent("command", true, true, window, 0,
                                 aEvent.ctrlKey, aEvent.altKey, aEvent.shiftKey,
-                                aEvent.metaKey, null);
+                                aEvent.metaKey, null, aEvent.mozInputSource);
       aEvent.currentTarget.dispatchEvent(cmdEvent);
     });
 
diff --git a/layout/xul/nsButtonBoxFrame.cpp b/layout/xul/nsButtonBoxFrame.cpp
index eefb0ab1d3fd..037c62dbb326 100644
--- a/layout/xul/nsButtonBoxFrame.cpp
+++ b/layout/xul/nsButtonBoxFrame.cpp
@@ -211,12 +211,19 @@ nsButtonBoxFrame::DoMouseClick(WidgetGUIEvent* aEvent, bool aTrustEvent)
   bool isControl = false;
   bool isAlt = false;
   bool isMeta = false;
+  uint16_t inputSource = nsIDOMMouseEvent::MOZ_SOURCE_UNKNOWN;
+
   if(aEvent) {
     WidgetInputEvent* inputEvent = aEvent->AsInputEvent();
     isShift = inputEvent->IsShift();
     isControl = inputEvent->IsControl();
     isAlt = inputEvent->IsAlt();
     isMeta = inputEvent->IsMeta();
+
+    WidgetMouseEventBase* mouseEvent = aEvent->AsMouseEventBase();
+    if (mouseEvent) {
+      inputSource = mouseEvent->inputSource;
+    }
   }
 
   // Have the content handle the event, propagating it according to normal DOM rules.
@@ -226,6 +233,6 @@ nsButtonBoxFrame::DoMouseClick(WidgetGUIEvent* aEvent, bool aTrustEvent)
                                        aEvent ?
                                          aEvent->IsTrusted() : aTrustEvent,
                                        nullptr, shell,
-                                       isControl, isAlt, isShift, isMeta);
+                                       isControl, isAlt, isShift, isMeta, inputSource);
   }
 }
diff --git a/layout/xul/nsResizerFrame.cpp b/layout/xul/nsResizerFrame.cpp
index 6a8f69912a7b..097dfed1a796 100644
--- a/layout/xul/nsResizerFrame.cpp
+++ b/layout/xul/nsResizerFrame.cpp
@@ -533,6 +533,23 @@ nsResizerFrame::GetDirection()
 void
 nsResizerFrame::MouseClicked(WidgetMouseEvent* aEvent)
 {
+  bool isTrusted = false;
+  bool isShift = false;
+  bool isControl = false;
+  bool isAlt = false;
+  bool isMeta = false;
+  uint16_t inputSource = nsIDOMMouseEvent::MOZ_SOURCE_UNKNOWN;
+
+  if(aEvent) {
+    isShift = aEvent->IsShift();
+    isControl = aEvent->IsControl();
+    isAlt = aEvent->IsAlt();
+    isMeta = aEvent->IsMeta();
+    inputSource = aEvent->inputSource;
+  }
+
   // Execute the oncommand event handler.
-  nsContentUtils::DispatchXULCommand(mContent, aEvent && aEvent->IsTrusted());
+  nsContentUtils::DispatchXULCommand(mContent, isTrusted, nullptr,
+                                     nullptr, isControl, isAlt,
+                                     isShift, isMeta, inputSource);
 }
diff --git a/layout/xul/nsTitleBarFrame.cpp b/layout/xul/nsTitleBarFrame.cpp
index c0ca37df0258..4f948a34ba86 100644
--- a/layout/xul/nsTitleBarFrame.cpp
+++ b/layout/xul/nsTitleBarFrame.cpp
@@ -167,6 +167,23 @@ nsTitleBarFrame::HandleEvent(nsPresContext* aPresContext,
 void
 nsTitleBarFrame::MouseClicked(WidgetMouseEvent* aEvent)
 {
+  bool isTrusted = false;
+  bool isShift = false;
+  bool isControl = false;
+  bool isAlt = false;
+  bool isMeta = false;
+  uint16_t inputSource = nsIDOMMouseEvent::MOZ_SOURCE_UNKNOWN;
+
+  if(aEvent) {
+    isShift = aEvent->IsShift();
+    isControl = aEvent->IsControl();
+    isAlt = aEvent->IsAlt();
+    isMeta = aEvent->IsMeta();
+    inputSource = aEvent->inputSource;
+  }
+
   // Execute the oncommand event handler.
-  nsContentUtils::DispatchXULCommand(mContent, aEvent && aEvent->IsTrusted());
+  nsContentUtils::DispatchXULCommand(mContent, isTrusted, nullptr,
+                                     nullptr, isControl, isAlt,
+                                     isShift, isMeta, inputSource);
 }
diff --git a/mobile/android/chrome/content/SelectHelper.js b/mobile/android/chrome/content/SelectHelper.js
index bbb15ba47e1a..f3d61a1f16df 100644
--- a/mobile/android/chrome/content/SelectHelper.js
+++ b/mobile/android/chrome/content/SelectHelper.js
@@ -154,7 +154,7 @@ var SelectHelper = {
     let win = element.ownerGlobal;
     let event = element.ownerDocument.createEvent("XULCommandEvent");
     event.initCommandEvent("command", true, true, element.defaultView, 0,
-        false, false, false, false, null);
+        false, false, false, false, null, 0);
     win.setTimeout(function() {
       element.dispatchEvent(event);
     }, 0);
diff --git a/widget/cocoa/nsMenuUtilsX.mm b/widget/cocoa/nsMenuUtilsX.mm
index 3e7b2a12ab17..4adb24f8f5f9 100644
--- a/widget/cocoa/nsMenuUtilsX.mm
+++ b/widget/cocoa/nsMenuUtilsX.mm
@@ -40,7 +40,7 @@ void nsMenuUtilsX::DispatchCommandTo(nsIContent* aTargetContent)
                                                true, true,
                                                doc->GetInnerWindow(), 0,
                                                false, false, false,
-                                               false, nullptr))) {
+                                               false, nullptr, 0))) {
       event->SetTrusted(true);
       bool dummy;
       aTargetContent->DispatchEvent(event, &dummy);