--- a/view/nsView.cpp
+++ b/view/nsView.cpp
@@ -229,27 +229,16 @@ bool nsView::IsEffectivelyVisible()
 {
   for (nsView* v = this; v; v = v->mParent) {
     if (v->GetVisibility() == nsViewVisibility_kHide)
       return false;
   }
   return true;
 }
 
-uint32_t nsView::GetParentWindowScaleFactor()
-{
-  uint32_t scaleFactor = 1;
-  nsIWidget* parentWidget =
-    GetParent() ? GetParent()->GetNearestWidget(nullptr) : nullptr;
-  if (parentWidget) {
-    scaleFactor = parentWidget->RoundsWidgetCoordinatesTo();
-  }
-  return scaleFactor;
-}
-
 LayoutDeviceIntRect nsView::CalcWidgetBounds(nsWindowType aType)
 {
   int32_t p2a = mViewManager->AppUnitsPerDevPixel();
 
   nsRect viewBounds(mDimBounds);
 
   nsView* parent = GetParent();
   nsIWidget* parentWidget = nullptr;
@@ -326,19 +315,17 @@ void nsView::DoResetWidgetBounds(bool aM
   MOZ_ASSERT(mWindow, "Why was this called??");
 
   // Hold this ref to make sure it stays alive.
   nsCOMPtr<nsIWidget> widget = mWindow;
 
   // Stash a copy of these and use them so we can handle this being deleted (say
   // from sync painting/flushing from Show/Move/Resize on the widget).
   LayoutDeviceIntRect newBounds;
-#if !defined(MOZ_WIDGET_GTK)
   RefPtr<nsDeviceContext> dx = mViewManager->GetDeviceContext();
-#endif
 
   nsWindowType type = widget->WindowType();
 
   LayoutDeviceIntRect curBounds = widget->GetClientBounds();
   bool invisiblePopup = type == eWindowType_popup &&
                         ((curBounds.IsEmpty() && mDimBounds.IsEmpty()) ||
                          mVis == nsViewVisibility_kHide);
 
@@ -368,25 +355,17 @@ void nsView::DoResetWidgetBounds(bool aM
   bool changedSize = curBounds.Size() != newBounds.Size();
 
   // Child views are never attached to top level widgets, this is safe.
 
   // Coordinates are converted to desktop pixels for window Move/Resize APIs,
   // because of the potential for device-pixel coordinate spaces for mixed
   // hidpi/lodpi screens to overlap each other and result in bad placement
   // (bug 814434).
-#if defined(MOZ_WIDGET_GTK)
-  // The GetDesktopToDeviceScale does not work under Wayland because we
-  // don't know the absolute position of the window in Wayland. We can
-  // use the same for X11, because it always returns 1 for both calls.
-  DesktopToLayoutDeviceScale scale = mozilla::DesktopToLayoutDeviceScale(
-    GetParentWindowScaleFactor());
-#else
   DesktopToLayoutDeviceScale scale = dx->GetDesktopToDeviceScale();
-#endif
 
   DesktopRect deskRect = newBounds / scale;
   if (changedPos) {
     if (changedSize && !aMoveOnly) {
       widget->ResizeClient(deskRect.X(), deskRect.Y(),
                            deskRect.Width(), deskRect.Height(),
                            aInvalidateChangedSize);
     } else {

--- a/view/nsView.h
+++ b/view/nsView.h
@@ -457,19 +457,16 @@ private:
 
   void ResetWidgetBounds(bool aRecurse, bool aForceSync);
   void AssertNoWindow();
 
   void NotifyEffectiveVisibilityChanged(bool aEffectivelyVisible);
 
   // Update the cached RootViewManager for all view manager descendents.
   void InvalidateHierarchy();
-  // Return current scale factor of the monitor where the parent window of the popup
-  // is mostly located.
-  uint32_t GetParentWindowScaleFactor();
 
   nsViewManager    *mViewManager;
   nsView           *mParent;
   nsCOMPtr<nsIWidget> mWindow;
   nsCOMPtr<nsIWidget> mPreviousWindow;
   nsView           *mNextSibling;
   nsView           *mFirstChild;
   nsIFrame         *mFrame;