diff --git a/widget/cocoa/nsCocoaWindow.mm b/widget/cocoa/nsCocoaWindow.mm
index a0f5e09c1586..67d9a105e7c0 100644
--- a/widget/cocoa/nsCocoaWindow.mm
+++ b/widget/cocoa/nsCocoaWindow.mm
@@ -2585,7 +2585,6 @@ already_AddRefed<nsIWidget> nsIWidget::CreateChildWindow() {
 - (NSPoint)FrameView__closeButtonOrigin;
 - (NSPoint)FrameView__fullScreenButtonOrigin;
 - (BOOL)FrameView__wantsFloatingTitlebar;
-- (NSRect)FrameView__unifiedToolbarFrame;
 @end
 
 @implementation NSView (FrameViewMethodSwizzling)
@@ -2611,18 +2610,6 @@ already_AddRefed<nsIWidget> nsIWidget::CreateChildWindow() {
   return NO;
 }
 
-- (NSRect)FrameView__unifiedToolbarFrame {
-  NSRect defaultFrame = [self FrameView__unifiedToolbarFrame];
-  if ([[self window] isKindOfClass:[ToolbarWindow class]]) {
-    CGFloat unifiedToolbarHeight = [(ToolbarWindow*)[self window] unifiedToolbarHeight];
-    CGFloat topEdge = NSMaxY(defaultFrame);
-    CGFloat bottomEdge = topEdge - unifiedToolbarHeight;
-    return NSMakeRect(defaultFrame.origin.x, bottomEdge, defaultFrame.size.width,
-                      unifiedToolbarHeight);
-  }
-  return defaultFrame;
-}
-
 @end
 
 static NSMutableSet* gSwizzledFrameViewClasses = nil;
@@ -2702,8 +2689,6 @@ static NSMutableSet* gSwizzledFrameViewClasses = nil;
       class_getMethodImplementation([NSView class], @selector(FrameView__fullScreenButtonOrigin));
   static IMP our_wantsFloatingTitlebar =
       class_getMethodImplementation([NSView class], @selector(FrameView__wantsFloatingTitlebar));
-  static IMP our_unifiedToolbarFrame =
-      class_getMethodImplementation([NSView class], @selector(FrameView__unifiedToolbarFrame));
 
   if (![gSwizzledFrameViewClasses containsObject:frameViewClass]) {
     // Either of these methods might be implemented in both a subclass of
@@ -2729,12 +2714,6 @@ static NSMutableSet* gSwizzledFrameViewClasses = nil;
       nsToolkit::SwizzleMethods(frameViewClass, @selector(_wantsFloatingTitlebar),
                                 @selector(FrameView__wantsFloatingTitlebar));
     }
-    IMP _unifiedToolbarFrame =
-        class_getMethodImplementation(frameViewClass, @selector(_unifiedToolbarFrame));
-    if (_unifiedToolbarFrame && _unifiedToolbarFrame != our_unifiedToolbarFrame) {
-      nsToolkit::SwizzleMethods(frameViewClass, @selector(_unifiedToolbarFrame),
-                                @selector(FrameView__unifiedToolbarFrame));
-    }
     [gSwizzledFrameViewClasses addObject:frameViewClass];
   }