diff --git a/ui/platform/linux/ui_utility_linux.h b/ui/platform/linux/ui_utility_linux.h
index d03c657..ce28a8e 100644
--- a/ui/platform/linux/ui_utility_linux.h
+++ b/ui/platform/linux/ui_utility_linux.h
@@ -29,9 +29,6 @@ inline void UpdateOverlayed(not_null<QWidget*> widget) {
 inline void ShowOverAll(not_null<QWidget*> widget, bool canFocus) {
 }
 
-inline void BringToBack(not_null<QWidget*> widget) {
-}
-
 inline void DisableSystemWindowResize(not_null<QWidget*> widget, QSize ratio) {
 }
 
diff --git a/ui/platform/mac/ui_utility_mac.mm b/ui/platform/mac/ui_utility_mac.mm
index 2b188d4..8ada998 100644
--- a/ui/platform/mac/ui_utility_mac.mm
+++ b/ui/platform/mac/ui_utility_mac.mm
@@ -77,11 +77,6 @@ void ShowOverAll(not_null<QWidget*> widget, bool canFocus) {
 	}
 }
 
-void BringToBack(not_null<QWidget*> widget) {
-	NSWindow *wnd = [reinterpret_cast<NSView*>(widget->winId()) window];
-	[wnd setLevel:NSModalPanelWindowLevel];
-}
-
 void DrainMainQueue() {
 #ifndef OS_MAC_STORE
 	_dispatch_main_queue_callback_4CF(nullptr);
diff --git a/ui/platform/mac/ui_window_mac.mm b/ui/platform/mac/ui_window_mac.mm
index a436206..557d623 100644
--- a/ui/platform/mac/ui_window_mac.mm
+++ b/ui/platform/mac/ui_window_mac.mm
@@ -137,6 +137,7 @@ private:
 	void init();
 	void initOpenGL();
 	void resolveWeakPointers();
+	void revalidateWeakPointers() const;
 	void initCustomTitle();
 
 	[[nodiscard]] Fn<void(bool)> toggleCustomTitleCallback();
@@ -148,6 +149,7 @@ private:
 
 	NSWindow * __weak _nativeWindow = nil;
 	NSView * __weak _nativeView = nil;
+	bool _hadNativeValues = false;
 
 	std::unique_ptr<LayerCreationChecker> _layerCreationChecker;
 
@@ -171,6 +173,7 @@ int WindowHelper::Private::customTitleHeight() const {
 }
 
 QRect WindowHelper::Private::controlsRect() const {
+	revalidateWeakPointers();
 	const auto button = [&](NSWindowButton type) {
 		auto view = [_nativeWindow standardWindowButton:type];
 		if (!view) {
@@ -201,6 +204,7 @@ QRect WindowHelper::Private::controlsRect() const {
 }
 
 bool WindowHelper::Private::checkNativeMove(void *nswindow) const {
+	revalidateWeakPointers();
 	if (_nativeWindow != nswindow
 		|| ([_nativeWindow styleMask] & NSWindowStyleMaskFullScreen) == NSWindowStyleMaskFullScreen) {
 		return false;
@@ -214,6 +218,7 @@ bool WindowHelper::Private::checkNativeMove(void *nswindow) const {
 }
 
 void WindowHelper::Private::activateBeforeNativeMove() {
+	revalidateWeakPointers();
 	[_nativeWindow makeKeyAndOrderFront:_nativeWindow];
 }
 
@@ -225,6 +230,7 @@ void WindowHelper::Private::setStaysOnTop(bool enabled) {
 }
 
 void WindowHelper::Private::setNativeTitleVisibility(bool visible) {
+	revalidateWeakPointers();
 	if (!_nativeWindow) {
 		return;
 	}
@@ -236,7 +242,11 @@ void WindowHelper::Private::close() {
 	const auto weak = Ui::MakeWeak(_owner->window());
 	QCloseEvent e;
 	qApp->sendEvent(_owner->window(), &e);
-	if (e.isAccepted() && weak && _nativeWindow) {
+	if (!e.isAccepted() || !weak) {
+		return;
+	}
+	revalidateWeakPointers();
+	if (_nativeWindow) {
 		[_nativeWindow close];
 	}
 }
@@ -253,6 +263,7 @@ Fn<void()> WindowHelper::Private::enforceStyleCallback() {
 }
 
 void WindowHelper::Private::enforceStyle() {
+	revalidateWeakPointers();
 	if (_nativeWindow && _customTitleHeight > 0) {
 		[_nativeWindow setStyleMask:[_nativeWindow styleMask] | NSWindowStyleMaskFullSizeContentView];
 	}
@@ -263,14 +274,24 @@ void WindowHelper::Private::initOpenGL() {
 }
 
 void WindowHelper::Private::resolveWeakPointers() {
-	_owner->window()->createWinId();
+	if (!_owner->window()->winId()) {
+		_owner->window()->createWinId();
+	}
 
 	_nativeView = reinterpret_cast<NSView*>(_owner->window()->winId());
 	_nativeWindow = _nativeView ? [_nativeView window] : nullptr;
+	_hadNativeValues = true;
 
 	Ensures(_nativeWindow != nullptr);
 }
 
+void WindowHelper::Private::revalidateWeakPointers() const {
+	if (_nativeWindow || !_hadNativeValues) {
+		return;
+	}
+	const_cast<Private*>(this)->resolveWeakPointers();
+}
+
 void WindowHelper::Private::initCustomTitle() {
 	if (![_nativeWindow respondsToSelector:@selector(contentLayoutRect)]
 		|| ![_nativeWindow respondsToSelector:@selector(setTitlebarAppearsTransparent:)]) {
diff --git a/ui/platform/ui_platform_utility.h b/ui/platform/ui_platform_utility.h
index 0bc0fd4..2d10077 100644
--- a/ui/platform/ui_platform_utility.h
+++ b/ui/platform/ui_platform_utility.h
@@ -25,7 +25,6 @@ void ReInitOnTopPanel(not_null<QWidget*> panel);
 
 void UpdateOverlayed(not_null<QWidget*> widget);
 void ShowOverAll(not_null<QWidget*> widget, bool canFocus = true);
-void BringToBack(not_null<QWidget*> widget);
 void IgnoreAllActivation(not_null<QWidget*> widget);
 void ClearTransientParent(not_null<QWidget*> widget);
 
diff --git a/ui/platform/win/ui_utility_win.h b/ui/platform/win/ui_utility_win.h
index 391acf2..b03df5c 100644
--- a/ui/platform/win/ui_utility_win.h
+++ b/ui/platform/win/ui_utility_win.h
@@ -32,9 +32,6 @@ inline void ReInitOnTopPanel(not_null<QWidget*> panel) {
 inline void ShowOverAll(not_null<QWidget*> widget, bool canFocus) {
 }
 
-inline void BringToBack(not_null<QWidget*> widget) {
-}
-
 inline void ClearTransientParent(not_null<QWidget*> widget) {
 }