diff --git a/gfx/layers/apz/src/AsyncPanZoomController.cpp b/gfx/layers/apz/src/AsyncPanZoomController.cpp
index f6abbf6fb045..400f37bb8c56 100644
--- a/gfx/layers/apz/src/AsyncPanZoomController.cpp
+++ b/gfx/layers/apz/src/AsyncPanZoomController.cpp
@@ -1013,8 +1013,8 @@ nsEventStatus AsyncPanZoomController::HandleDragEvent(const MouseInput& aEvent,
   CSSPoint scrollFramePoint = aEvent.mLocalOrigin / GetFrameMetrics().GetZoom();
   // The scrollbar can be transformed with the frame but the pres shell
   // resolution is only applied to the scroll frame.
-  CSSPoint scrollbarPoint = scrollFramePoint * GetFrameMetrics().GetPresShellResolution();
-  CSSRect cssCompositionBound = GetFrameMetrics().GetCompositionBounds() / GetFrameMetrics().GetZoom();
+  CSSPoint scrollbarPoint = scrollFramePoint * mFrameMetrics.GetPresShellResolution();
+  CSSRect cssCompositionBound = mFrameMetrics.CalculateCompositedRectInCssPixels();
 
   float mousePosition = GetAxisStart(aDragMetrics.mDirection, scrollbarPoint) -
                         aDragMetrics.mScrollbarDragOffset -
@@ -1023,34 +1023,31 @@ nsEventStatus AsyncPanZoomController::HandleDragEvent(const MouseInput& aEvent,
 
   float scrollMax = GetAxisEnd(aDragMetrics.mDirection, aDragMetrics.mScrollTrack);
   scrollMax -= node->GetScrollSize() /
-               GetAxisScale(aDragMetrics.mDirection, GetFrameMetrics().GetZoom()) *
-               GetFrameMetrics().GetPresShellResolution();
+               GetAxisScale(aDragMetrics.mDirection, mFrameMetrics.GetZoom()) *
+               mFrameMetrics.GetPresShellResolution();
 
   float scrollPercent = mousePosition / scrollMax;
 
   float minScrollPosition =
-    GetAxisStart(aDragMetrics.mDirection, GetFrameMetrics().GetScrollableRect().TopLeft());
+    GetAxisStart(aDragMetrics.mDirection, mFrameMetrics.GetScrollableRect().TopLeft());
   float maxScrollPosition =
-    GetAxisSize(aDragMetrics.mDirection, GetFrameMetrics().GetScrollableRect()) -
-    GetAxisSize(aDragMetrics.mDirection, GetFrameMetrics().GetCompositionBounds());
+    GetAxisSize(aDragMetrics.mDirection, mFrameMetrics.GetScrollableRect()) -
+    GetAxisSize(aDragMetrics.mDirection, mFrameMetrics.GetCompositionBounds());
   float scrollPosition = scrollPercent * maxScrollPosition;
 
   scrollPosition = std::max(scrollPosition, minScrollPosition);
   scrollPosition = std::min(scrollPosition, maxScrollPosition);
 
-  CSSPoint scrollOffset;
+  CSSPoint scrollOffset = mFrameMetrics.GetScrollOffset();
   if (aDragMetrics.mDirection == AsyncDragMetrics::HORIZONTAL) {
-    scrollOffset = CSSPoint(scrollPosition, 0);
+    scrollOffset.x = scrollPosition;
   } else {
-    scrollOffset = CSSPoint(0, scrollPosition);
+    scrollOffset.y = scrollPosition;
   }
   mFrameMetrics.SetScrollOffset(scrollOffset);
   ScheduleCompositeAndMaybeRepaint();
   UpdateSharedCompositorFrameMetrics();
 
-  // Here we consume the events. This means that the content scrollbars
-  // will only see the initial mouse down and the final mouse up.
-  // APZ will still update the scroll position.
   return nsEventStatus_eConsumeNoDefault;
 }