--- a/dom/base/nsGlobalWindow.cpp
+++ b/dom/base/nsGlobalWindow.cpp
@@ -973,16 +973,17 @@ NextWindowID();
 
 template<class T>
 nsPIDOMWindow<T>::nsPIDOMWindow(nsPIDOMWindowOuter *aOuterWindow)
 : mFrameElement(nullptr), mDocShell(nullptr), mModalStateDepth(0),
   mMutationBits(0), mIsDocumentLoaded(false),
   mIsHandlingResizeEvent(false), mIsInnerWindow(aOuterWindow != nullptr),
   mMayHavePaintEventListener(false), mMayHaveTouchEventListener(false),
   mMayHaveMouseEnterLeaveEventListener(false),
+  mMayHaveMouseMoveEventListener(false),
   mMayHavePointerEnterLeaveEventListener(false),
   mInnerObjectsFreed(false),
   mIsModalContentWindow(false),
   mIsActive(false), mIsBackground(false),
   mMediaSuspend(Preferences::GetBool("media.block-autoplay-until-in-foreground", true) ?
     nsISuspendedTypes::SUSPENDED_BLOCK : nsISuspendedTypes::NONE_SUSPENDED),
   mAudioMuted(false), mAudioVolume(1.0), mAudioCaptured(false),
   mDesktopModeViewport(false), mIsRootOuterWindow(false), mInnerWindow(nullptr),
@@ -2034,21 +2035,24 @@ nsGlobalWindow::FreeInnerObjects()
 {
   NS_ASSERTION(IsInnerWindow(), "Don't free inner objects on an outer window");
 
   if (mDoc && !nsContentUtils::IsSystemPrincipal(mDoc->NodePrincipal())) {
     EventTarget* win = this;
     EventTarget* html = mDoc->GetHtmlElement();
     EventTarget* body = mDoc->GetBodyElement();
 
+    bool mouseAware = AsInner()->HasMouseMoveEventListeners();
     bool keyboardAware = win->MayHaveAPZAwareKeyEventListener() ||
                          mDoc->MayHaveAPZAwareKeyEventListener() ||
                          (html && html->MayHaveAPZAwareKeyEventListener()) ||
                          (body && body->MayHaveAPZAwareKeyEventListener());
 
+    Telemetry::Accumulate(Telemetry::APZ_AWARE_MOUSEMOVE_LISTENERS,
+                          mouseAware ? 1 : 0);
     Telemetry::Accumulate(Telemetry::APZ_AWARE_KEY_LISTENERS,
                           keyboardAware ? 1 : 0);
   }
 
   // Make sure that this is called before we null out the document and
   // other members that the window destroyed observers could
   // re-create.
   NotifyDOMWindowDestroyed(this);

--- a/dom/base/nsNodeUtils.cpp
+++ b/dom/base/nsNodeUtils.cpp
@@ -534,16 +534,19 @@ nsNodeUtils::CloneAndAdopt(nsINode *aNod
         if (elm) {
           window->SetMutationListeners(elm->MutationListenerBits());
           if (elm->MayHavePaintEventListener()) {
             window->SetHasPaintEventListeners();
           }
           if (elm->MayHaveTouchEventListener()) {
             window->SetHasTouchEventListeners();
           }
+          if (elm->MayHaveMouseMoveEventListener()) {
+            window->SetHasMouseMoveEventListeners();
+          }
           if (elm->MayHaveMouseEnterLeaveEventListener()) {
             window->SetHasMouseEnterLeaveEventListeners();
           }
           if (elm->MayHavePointerEnterLeaveEventListener()) {
             window->SetHasPointerEnterLeaveEventListeners();
           }
         }
       }

--- a/dom/base/nsPIDOMWindow.h
+++ b/dom/base/nsPIDOMWindow.h
@@ -664,16 +664,17 @@ protected:
   uint32_t               mMutationBits;
 
   bool                   mIsDocumentLoaded;
   bool                   mIsHandlingResizeEvent;
   bool                   mIsInnerWindow;
   bool                   mMayHavePaintEventListener;
   bool                   mMayHaveTouchEventListener;
   bool                   mMayHaveMouseEnterLeaveEventListener;
+  bool                   mMayHaveMouseMoveEventListener;
   bool                   mMayHavePointerEnterLeaveEventListener;
 
   // Used to detect whether we have called FreeInnerObjects() (e.g. to ensure
   // that a call to ResumeTimeouts() after FreeInnerObjects() does nothing).
   // This member is only used by inner windows.
   bool                   mInnerObjectsFreed;
 
 
@@ -811,16 +812,34 @@ public:
       return;
     }
 
     mMutationBits |= aType;
   }
 
   /**
    * Call this to check whether some node (this window, its document,
+   * or content in that document) has or had a mousemove event listener.
+   */
+  bool HasMouseMoveEventListeners()
+  {
+    return mMayHaveMouseMoveEventListener;
+  }
+
+  /**
+   * Call this to indicate that some node (this window, its document,
+   * or content in that document) has or had a mousemove event listener.
+   */
+  void SetHasMouseMoveEventListeners()
+  {
+    mMayHaveMouseMoveEventListener = true;
+  }
+
+  /**
+   * Call this to check whether some node (this window, its document,
    * or content in that document) has a mouseenter/leave event listener.
    */
   bool HasMouseEnterLeaveEventListeners()
   {
     return mMayHaveMouseEnterLeaveEventListener;
   }
 
   /**

--- a/dom/events/EventListenerManager.cpp
+++ b/dom/events/EventListenerManager.cpp
@@ -122,16 +122,17 @@ IsWebkitPrefixSupportEnabled()
 
 EventListenerManagerBase::EventListenerManagerBase()
   : mNoListenerForEvent(eVoidEvent)
   , mMayHavePaintEventListener(false)
   , mMayHaveMutationListeners(false)
   , mMayHaveCapturingListeners(false)
   , mMayHaveSystemGroupListeners(false)
   , mMayHaveTouchEventListener(false)
+  , mMayHaveMouseMoveEventListener(false)
   , mMayHaveMouseEnterLeaveEventListener(false)
   , mMayHavePointerEnterLeaveEventListener(false)
   , mMayHaveAPZAwareKeyEventListener(false)
   , mMayHaveKeyEventListener(false)
   , mMayHaveInputOrCompositionEventListener(false)
   , mClearingListeners(false)
   , mIsMainThreadELM(NS_IsMainThread())
 {
@@ -417,16 +418,21 @@ EventListenerManager::AddEventListenerIn
     }
   } else if (aTypeAtom == nsGkAtoms::oncompositionend ||
              aTypeAtom == nsGkAtoms::oncompositionstart ||
              aTypeAtom == nsGkAtoms::oncompositionupdate ||
              aTypeAtom == nsGkAtoms::oninput) {
     if (!aFlags.mInSystemGroup) {
       mMayHaveInputOrCompositionEventListener = true;
     }
+  } else if (aTypeAtom == nsGkAtoms::onmousemove) {
+    mMayHaveMouseMoveEventListener = true;
+    if (nsPIDOMWindowInner* window = GetInnerWindowForTarget()) {
+      window->SetHasMouseMoveEventListeners();
+    }
   }
 
   if (IsApzAwareListener(listener)) {
     ProcessApzAwareEventListenerAdd();
   }
 
   if (mTarget) {
     if (aTypeAtom) {

--- a/dom/events/EventListenerManager.h
+++ b/dom/events/EventListenerManager.h
@@ -156,24 +156,25 @@ protected:
   EventListenerManagerBase();
 
   EventMessage mNoListenerForEvent;
   uint16_t mMayHavePaintEventListener : 1;
   uint16_t mMayHaveMutationListeners : 1;
   uint16_t mMayHaveCapturingListeners : 1;
   uint16_t mMayHaveSystemGroupListeners : 1;
   uint16_t mMayHaveTouchEventListener : 1;
+  uint16_t mMayHaveMouseMoveEventListener : 1;
   uint16_t mMayHaveMouseEnterLeaveEventListener : 1;
   uint16_t mMayHavePointerEnterLeaveEventListener : 1;
   uint16_t mMayHaveAPZAwareKeyEventListener : 1;
   uint16_t mMayHaveKeyEventListener : 1;
   uint16_t mMayHaveInputOrCompositionEventListener : 1;
   uint16_t mClearingListeners : 1;
   uint16_t mIsMainThreadELM : 1;
-  // uint16_t mUnused : 4;
+  // uint16_t mUnused : 3;
 };
 
 /*
  * Event listener manager
  */
 
 class EventListenerManager final : public EventListenerManagerBase
 {
@@ -435,16 +436,18 @@ public:
   bool MayHavePaintEventListener() { return mMayHavePaintEventListener; }
 
   /**
    * Returns true if there may be a touch event listener registered,
    * false if there definitely isn't.
    */
   bool MayHaveTouchEventListener() { return mMayHaveTouchEventListener; }
 
+  bool MayHaveMouseMoveEventListener() { return mMayHaveMouseMoveEventListener; }
+
   bool MayHaveMouseEnterLeaveEventListener() { return mMayHaveMouseEnterLeaveEventListener; }
   bool MayHavePointerEnterLeaveEventListener() { return mMayHavePointerEnterLeaveEventListener; }
 
   bool MayHaveAPZAwareKeyEventListener() const { return mMayHaveAPZAwareKeyEventListener; }
 
   /**
    * Returns true if there may be a key event listener (keydown, keypress,
    * or keyup) registered, or false if there definitely isn't.

--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -10430,16 +10430,23 @@
   },
   "APZ_AWARE_KEY_LISTENERS": {
     "alert_emails": ["rhunt@mozilla.com"],
     "bug_numbers": [1352654],
     "expires_in_version": "58",
     "kind": "boolean",
     "description": "The percentage of pages with a non-passive key event on the path to the root scrolling element that would disable APZ key scrolling."
   },
+  "APZ_AWARE_MOUSEMOVE_LISTENERS": {
+    "alert_emails": ["rhunt@mozilla.com"],
+    "bug_numbers": [1352654],
+    "expires_in_version": "58",
+    "kind": "boolean",
+    "description": "The percentage of pages with a mousemove listener anywhere in the document that would disable APZ key scrolling."
+  },
   "SCROLL_INPUT_METHODS": {
     "alert_emails": ["botond@mozilla.com"],
     "bug_numbers": [1238137],
     "expires_in_version": "60",
     "kind": "enumerated",
     "n_values": 64,
     "description": "Count of scroll actions triggered by different input methods. See gfx/layers/apz/util/ScrollInputMethods.h for a list of possible values and their meanings."
   },