On Windows, in SDL 3.2.8, there is a delay in updating the rendering viewport after minimizing multiple windows.

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This test code reproduces a bug where minimizing window, maximizing window1, and then restoring window causes a delay in updating the rendering viewport of window.

int main(int argc, char* argv[]) {
SDL_Init(SDL_INIT_VIDEO);
SDL_Window* window = SDL_CreateWindow("SDL", 640.00f, 540.00f, SDL_WINDOW_HIGH_PIXEL_DENSITY | SDL_WINDOW_RESIZABLE | SDL_WINDOW_BORDERLESS | SDL_WINDOW_TRANSPARENT);

SDL_PropertiesID m_props = SDL_CreateProperties();
SDL_SetPointerProperty(m_props, SDL_PROP_RENDERER_CREATE_WINDOW_POINTER, window);
SDL_SetNumberProperty(m_props, SDL_PROP_RENDERER_CREATE_OUTPUT_COLORSPACE_NUMBER, SDL_COLORSPACE_SRGB);
SDL_SetNumberProperty(m_props, SDL_PROP_RENDERER_CREATE_PRESENT_VSYNC_NUMBER, 2); 
SDL_SetStringProperty(m_props, SDL_PROP_RENDERER_CREATE_NAME_STRING, "direct3d11");

SDL_Renderer* renderer = SDL_CreateRendererWithProperties(m_props);
if (!renderer) {
	std::cerr << "SDL_CreateRenderer Error: " << SDL_GetError() << std::endl;
	SDL_DestroyWindow(window);
	SDL_Quit();
	return 1;
}

SDL_Window* window1 = SDL_CreateWindow("SDL1", 640.00f, 540.00f, SDL_WINDOW_HIGH_PIXEL_DENSITY | SDL_WINDOW_RESIZABLE | SDL_WINDOW_BORDERLESS | SDL_WINDOW_TRANSPARENT);

SDL_PropertiesID m_props1 = SDL_CreateProperties();
SDL_SetPointerProperty(m_props1, SDL_PROP_RENDERER_CREATE_WINDOW_POINTER, window1);
SDL_SetNumberProperty(m_props1, SDL_PROP_RENDERER_CREATE_OUTPUT_COLORSPACE_NUMBER, SDL_COLORSPACE_SRGB);
SDL_SetNumberProperty(m_props1, SDL_PROP_RENDERER_CREATE_PRESENT_VSYNC_NUMBER, 2); 
SDL_SetStringProperty(m_props1, SDL_PROP_RENDERER_CREATE_NAME_STRING, "direct3d11");

SDL_Renderer* renderer1 = SDL_CreateRendererWithProperties(m_props1);
if (!renderer1) {
	std::cerr << "SDL_CreateRenderer Error: " << SDL_GetError() << std::endl;
	SDL_DestroyWindow(window);
	SDL_Quit();
	return 1;
}

SDL_MinimizeWindow(window);
SDL_MaximizeWindow(window1);
SDL_RestoreWindow(window);
//SDL_RestoreWindow(window1);

bool running = true;
SDL_Rect t_rect;
SDL_Event event;
while (running) {
	while (SDL_PollEvent(&event)) {
		if (event.type == SDL_EVENT_WINDOW_RESTORED) {
			if (window == SDL_GetWindowFromEvent(&event)) {
				SDL_Rect t_rect;
				SDL_GetRenderViewport(renderer, &t_rect);
				printf("SDL_EVENT_WINDOW_RESTORED %d %d %d %d\n", t_rect.x, t_rect.y, t_rect.w, t_rect.h);
				SDL_GetWindowSize(window, &t_rect.w, &t_rect.h);
				printf("SDL_GetWindowSize %d %d\n", t_rect.w, t_rect.h);
			}
		}
	}

	SDL_SetRenderDrawColor(renderer, 0, 0, 255, 255);
	SDL_RenderClear(renderer);
	SDL_RenderPresent(renderer);

	SDL_SetRenderDrawColor(renderer1, 0, 0, 255, 255);
	SDL_RenderClear(renderer1);
	SDL_RenderPresent(renderer1);
}

SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();

return 0;

}

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