wl_surface: set output to dummy when unmapping

src/ifs/wl_surface.rs

@@ -906,6 +906,12 @@ impl WlSurface {
 
     fn unset_ext(&self) {
         self.ext.set(self.client.state.none_surface_ext.clone());
+        self.set_dummy_output();
+    }
+
+    fn set_dummy_output(&self) {
+        let dummy_output = self.client.state.dummy_output.get().unwrap();
+        self.set_output(&dummy_output, NodeLocation::Output(dummy_output.id));
     }
 
     fn calculate_extents(&self, propagate: bool) {

src/ifs/wl_surface/xdg_surface.rs

@@ -433,6 +433,11 @@ impl XdgSurface {
             f(&popup.popup);
         }
     }
+
+    fn unset_ext(&self) {
+        self.ext.set(None);
+        self.surface.set_dummy_output();
+    }
 }
 
 impl XdgSurfaceRequestHandler for XdgSurface {

src/ifs/wl_surface/xdg_surface/xdg_popup.rs

@@ -229,7 +229,7 @@ impl XdgPopupRequestHandler for XdgPopup {
 
     fn destroy(&self, _req: Destroy, _slf: &Rc<Self>) -> Result<(), Self::Error> {
         self.destroy_node();
-        self.xdg.ext.set(None);
+        self.xdg.unset_ext();
         self.xdg.surface.client.remove_obj(self)?;
         Ok(())
     }

src/ifs/wl_surface/xdg_surface/xdg_toplevel.rs

@@ -256,7 +256,7 @@ impl XdgToplevelRequestHandler for XdgToplevel {
 
     fn destroy(&self, _req: Destroy, _slf: &Rc<Self>) -> Result<(), Self::Error> {
         self.tl_destroy();
-        self.xdg.ext.set(None);
+        self.xdg.unset_ext();
         {
             let mut children = self.children.borrow_mut();
             let parent = self.parent.get();