diff --git a/lcl/interfaces/cocoa/cocoa_extra.pas b/lcl/interfaces/cocoa/cocoa_extra.pas
index e9850c2aef..29680590ee 100644
--- a/lcl/interfaces/cocoa/cocoa_extra.pas
+++ b/lcl/interfaces/cocoa/cocoa_extra.pas
@@ -60,8 +60,11 @@ type
   end;
 
   NSWindowFix = objccategory external (NSWindow)
+    // 10.4-10.7
+    function userSpaceScaleFactor: CGFloat; message 'userSpaceScaleFactor'; //deprecated
     // 10.7+
     procedure toggleFullScreen(sender: id); message 'toggleFullScreen:';
+    function backingScaleFactor: CGFloat; message 'backingScaleFactor';
   end;
 
   {// private since 10.5, doesn't seam to do anything in 10.10
diff --git a/lcl/interfaces/cocoa/cocoaprivate.pp b/lcl/interfaces/cocoa/cocoaprivate.pp
index 9a87ea4d6f..7dbbaf974c 100644
--- a/lcl/interfaces/cocoa/cocoaprivate.pp
+++ b/lcl/interfaces/cocoa/cocoaprivate.pp
@@ -406,10 +406,6 @@ type
     procedure mouseMoved(event: NSEvent); override;
   end;
 
-  NSWindow = objcclass external(CocoaAll.NSWindow)
-    function backingScaleFactor: CGFloat; message 'backingScaleFactor';
-  end;
-
   { TCocoaWindow }
 
   TCocoaWindowContent = objcclass;
diff --git a/lcl/interfaces/cocoa/cocoawscommon.pas b/lcl/interfaces/cocoa/cocoawscommon.pas
index 5931641ea3..bf6e6e8d2d 100644
--- a/lcl/interfaces/cocoa/cocoawscommon.pas
+++ b/lcl/interfaces/cocoa/cocoawscommon.pas
@@ -8,7 +8,7 @@ interface
 
 uses
   Types,
-  CGGeometry, CocoaAll,
+  CGGeometry, CocoaAll, cocoa_extra,
   Classes, Controls, SysUtils,
   //
   WSControls, LCLType, LMessages, LCLProc, Graphics, Forms,
@@ -1372,11 +1372,29 @@ end;
 
 class function TCocoaWSWinControl.GetCanvasScaleFactor(const AControl: TControl
   ): Double;
+var
+  obj: NSObject;
+  win: NSWindow;
 begin
+  win := nil;
+  Result := 1;
+
   if TWinControl(AControl).HandleAllocated then
-    Result := TCocoaWindow(TWinControl(AControl).Handle).backingScaleFactor // ToDo: use userSpaceScaleFactor for Mac OSX 10.6
-  else
-    Result := 1;
+  begin
+    obj := NSObject(TWinControl(AControl).Handle);
+    if obj.isKindOfClass_(NSView) then
+      win := NSView(obj).window
+    else if obj.isKindOfClass_(NSWindow) then
+      win := NSWindow(obj);
+  end;
+
+  if Assigned(win) then
+  begin
+    if win.respondsToSelector( NSSelectorFromString(NSSTR('backingScaleFactor'))) then
+      Result := win.backingScaleFactor
+    else if win.respondsToSelector( NSSelectorFromString(NSSTR('userSpaceScaleFactor'))) then // for older OSX
+      Result := win.userSpaceScaleFactor;
+  end;
 end;
 
 class procedure TCocoaWSWinControl.SetText(const AWinControl: TWinControl; const AText: String);