diff --git a/internal/ui/ui_cbackend.go b/internal/ui/ui_cbackend.go
index 96fe972ea..3f7ec859e 100644
--- a/internal/ui/ui_cbackend.go
+++ b/internal/ui/ui_cbackend.go
@@ -143,6 +143,6 @@ func (*userInterfaceImpl) Input() *Input {
 	return &theUI.input
 }
 
-func (*userInterfaceImpl) Window() *Window {
-	return &Window{}
+func (*userInterfaceImpl) Window() Window {
+	return &nullWindow{}
 }