diff --git a/src/app.rs b/src/app.rs
index db0b309..f17e5b2 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -240,13 +240,17 @@ impl ApplicationHandler<UserEvent> for Application {
         }
         self.viewports
             .retain(|k, _| !inactive_viewports.contains(k));
-        match self.viewports.get(&ViewportId::ROOT) {
+        match self.viewports.get(&viewport_id) {
             Some(viewport) => {
                 if queue_redraw {
                     viewport.window.request_redraw();
                 }
             }
-            None => event_loop.exit(),
+            None => {
+                if viewport_id == ViewportId::ROOT {
+                    event_loop.exit();
+                }
+            }
         }
     }
 
@@ -480,7 +484,9 @@ impl Viewport {
         if let Some(icon) = icon {
             builder = builder.with_icon(icon);
         }
-        let (window, state) = create_window_and_state(&ctx, event_loop, &builder, &mut painter);
+        let viewport_id = app.viewport_id();
+        let (window, state) =
+            create_window_and_state(&ctx, viewport_id, event_loop, &builder, &mut painter);
         egui_winit::update_viewport_info(&mut info, &ctx, &window, true);
 
         let render_state = painter.render_state();
@@ -522,7 +528,7 @@ impl Viewport {
                     (NonZero::new(size.width), NonZero::new(size.height))
                 {
                     self.painter
-                        .on_window_resized(ViewportId::ROOT, width, height);
+                        .on_window_resized(self.app.viewport_id(), width, height);
                 }
                 None
             }
@@ -533,14 +539,16 @@ impl Viewport {
     }
 
     fn redraw(&mut self, event_loop: &ActiveEventLoop) -> Option<Action> {
+        let viewport_id = self.app.viewport_id();
         let mut input = self.state.take_egui_input(&self.window);
-        input.viewports = std::iter::once((ViewportId::ROOT, self.info.clone())).collect();
+        input.viewports = std::iter::once((viewport_id, self.info.clone())).collect();
+        input.viewport_id = viewport_id;
         let mut output = self.ctx.run_ui(input, |ui| {
             self.app.show(ui);
         });
         let clipped_primitives = self.ctx.tessellate(output.shapes, output.pixels_per_point);
         self.painter.paint_and_update_textures(
-            ViewportId::ROOT,
+            viewport_id,
             output.pixels_per_point,
             [0.0, 0.0, 0.0, 0.0],
             &clipped_primitives,
@@ -551,14 +559,19 @@ impl Viewport {
         self.state
             .handle_platform_output(&self.window, output.platform_output);
 
-        let Some(mut viewport_output) = output.viewport_output.remove(&ViewportId::ROOT) else {
+        let Some(mut viewport_output) = output.viewport_output.remove(&viewport_id) else {
             return Some(Action::Close);
         };
 
         let (mut deferred_commands, recreate) = self.builder.patch(viewport_output.builder);
         if recreate {
-            let (window, state) =
-                create_window_and_state(&self.ctx, event_loop, &self.builder, &mut self.painter);
+            let (window, state) = create_window_and_state(
+                &self.ctx,
+                viewport_id,
+                event_loop,
+                &self.builder,
+                &mut self.painter,
+            );
             egui_winit::update_viewport_info(&mut self.info, &self.ctx, &window, true);
             self.window = window;
             self.state = state;
@@ -613,16 +626,17 @@ pub enum Action {
 
 fn create_window_and_state(
     ctx: &Context,
+    viewport_id: ViewportId,
     event_loop: &ActiveEventLoop,
     builder: &ViewportBuilder,
     painter: &mut egui_wgpu::winit::Painter,
 ) -> (Arc<Window>, egui_winit::State) {
-    pollster::block_on(painter.set_window(ViewportId::ROOT, None)).unwrap();
+    pollster::block_on(painter.set_window(viewport_id, None)).unwrap();
     let window = Arc::new(egui_winit::create_window(ctx, event_loop, builder).unwrap());
-    pollster::block_on(painter.set_window(ViewportId::ROOT, Some(window.clone()))).unwrap();
+    pollster::block_on(painter.set_window(viewport_id, Some(window.clone()))).unwrap();
     let state = egui_winit::State::new(
         ctx.clone(),
-        ViewportId::ROOT,
+        viewport_id,
         event_loop,
         Some(window.scale_factor() as f32),
         event_loop.system_theme(),